III. FOUNDATIONS OF MATHEMATICS
11. The
comparison between mathematics and a game
‘What are we taking away from mathematics when we
say it is only a game (or it is a game)?’
mathematics as an action is a game – that is an
action in accordance with rules –
the propositions used in the game – and the
propositions that function as ‘rules’ of the game –
as with any
proposal – any proposition – are open to question – open to doubt – are
uncertain
we take nothing away from mathematics when we say
it is a game – any rule governed activity is properly termed a ‘game’ – this is the practise of mathematics
the theory of mathematics is the proposal – the
propositions used in the game –
these proposals – these propositions – are open to
question – to doubt – are uncertain
when we play
a game – we suspend questioning – suspend doubt – in order to play
when we question and doubt – we do not play – we question and doubt –
there are no rules to uncertainty
‘A game in contrast to what? What are we awarding
to mathematics if we say it isn’t a game, its propositions have sense?’
a game in contrast to what?
a game in contrast to non-rule governed
propositional action – non-rule governed propositional behaviour
mathematics is a game – as mathematics is practised –
as to the sense of a mathematical proposition –
the sense of mathematical propositions – as with
any proposal – any proposition –
is open to question – open to doubt – is uncertain
subjecting mathematical propositions to question –
to doubt – recognizing their uncertainty –
is not doing mathematics – it is doing logic
‘The sense outside the proposition.
What concern is it of ours? Where does it manifest
itself and what can we do with it? (To the question “what is the sense of this
proposition?” the answer is a proposition.)
(“But a mathematical proposition does express a
thought” – What thought? –.)’
our proposals – our propositions – make known – make sense –
there is no sense out side of propositional reality
–
outside of propositional reality is the unknown
‘to the question ‘what is the sense of this
proposition?’ the answer is a proposition’
yes – exactly –
and any proposal – any proposition – is open to
question – open to doubt –
sense is uncertain
when we say a mathematical proposition expresses a
thought – we are putting forward a proposal – an explanatory proposal – of the
mathematical proposition
it may prove useful to some to operate with such an
explanatory proposal –
that is neither here nor there really –
for any such proposal is open to question – open to
doubt – uncertain –
there are no
rules for how we account for our propositions – there are no rules for how we account for reality
– for the unknown
‘Can it be expressed by another proposition? Or
only by this proposition? – Or not at all? In that case it is no concern of
ours.’
I take it this means –
can the sense of a mathematical proposition be
expressed by another proposition?
one could say that the ‘sense’ of a mathematical
proposition is expressed in a painting for example – or some other work of art
it is all a matter of interpretation – but any such
interpretation – is of course – open to question
I would say if you are doing mathematics – it would
only be of peripheral interest that some
proposition of the mathematics is expressed – ‘illustrated’ in some other
propositional form –
and the other thing is – just what is to be
regarded as a mathematical proposition – might depend on who you are talking to
‘Do you simply want to distinguish mathematical
propositions from other constructions, such as hypotheses? You are right to do
so: there is no doubt there is a distinction.’
for practical purposes – yes we distinguish
propositions – proposition types – proposition uses
the logic of the matter is entirely different –
there is no logical distinction between a proposal
– be it described as mathematical –
or whatever – and the proposal described
as an hypothesis –
these descriptions ‘mathematical’ and ‘hypothesis’
– have to do with context – ways of practise
any proposal – however described – is open to
question – open to doubt – is uncertain
to say there is no doubt – is rubbish –
it is in fact a denial of logic
‘If you want to say that mathematics is played like
chess or patience and the point of it is like winning or coming out, that is
manifestly incorrect.’
if you want to know how mathematics is played –
start by asking those who play it –
and any proposal they put forward will be of
interest
mathematics is not ‘chess’ or ‘patience’ – yes
chess or patience could be described in mathematical terms – but they are different rule governed activities –
different games
the point of anything – of any propositional action
– is open to question – open to doubt –is uncertain
‘If you say the mental processes accompanying the
use of mathematical symbols are different from those accompanying chess, I
wouldn’t know what to say about that’
the proposal of mental processes and all that
involves is a description of
propositional action –
it is one proposal – one explanatory proposal –
among any number that can – that have been advanced to account for
propositional action –
it is the doing
of mathematics that is important –
how you explain – account for mathematical
propositions – mathematical propositional action – is frankly a matter of philosophical
prejudice
and it’s only real only function is to provide speculative
context for the propositional action
and any such speculation if it enables you to do mathematics – if it gets you going – is
useful
once you understand that any proposition – any
propositional action is open to question – open to doubt – is uncertain – the differences between propositional
practises – are logically irrelevant
–
you can leave such differences to sociologists and
their progeny – modern French philosophers
‘In chess there are some positions that are
impossible although each individual piece is in a permissible position. (E.g.
if all the pawns are still in their initial position, but a bishop is already
in play.) But one could imagine a game in which a record was kept of the number
of moves from the beginning of the game and then there would be certain
positions which could not occur after n moves and yet one could not read off
from a position by itself whether or not it was a possible nth position.’
‘certain positions that could not occur after n
moves’ – is a rule
‘and yet one could not read off from a position by
itself whether or not it was a possible nth position’
there is no ‘position by itself’ – any place
on the board is only a ‘position’ in terms of the rules of the game
the moves in chess – are expressions of the rules
of chess – the rules of the game
‘What we do in games must correspond to what we do
in calculating. (I mean: it’s there that the correspondence must be, or again,
that’s the way that the two must be correlated with each other.)’
calculating is a game –
calculating is a sign-game – a language-game –
it is a paradigm of game-playing
is all rule governed activity – calculating?
of course other games can be described in terms of
calculating –
but can they also be described in other terms?
is the chess player’s move a calculation – a
spontaneous action – a careless action etc.?
the point is that a rule governed activity can
be described variously –
and any description is open to question – open to
doubt – is logically speaking uncertain
‘Is mathematics about signs on paper? No more than
chess is about wooden pieces.
When we talk about the sense of mathematical
propositions, or what they are about, we are using a false picture. Here too I
mean it looks as if there are inessential, arbitrary signs which have an
essential element in common, namely sense.’
mathematics is about proposals – propositions –
signs on paper?
I don’t know that paper is essential – but what
mathematics – what proposal – do you have without signs?
and as to how signs are expressed – that is
‘inessential’
as to ‘sense’ –
sense here really has to be a catch phrase for
‘significance’
yes signs have – can have – significance –
just what that significance is – what is proposed –
will be open to question – open to doubt –
the matter is – logically speaking – uncertain
in different propositional practises – there will
be different accounts of significance
what signs have in common –
is that that they are proposed
‘Since mathematics is a calculus and hence isn’t
really about anything, there isn’t any metamathematics.’
just what mathematics is – and what it is about –
is open to question – open to doubt is uncertain
by all means have a view – but keep an open mind
can you operate a calculus without an
interpretation?
you may think you do – but every sign in a calculus
has a logical history – a history of interpretation
and any interpretation – any ‘metamathematics’ – if
you wish to call it that – is logically speaking – open to question – open to
doubt – is uncertain
‘What is the relation between a chess problem and a
game of chess? – It is clear that chess problems correspond to arithmetical
problems, indeed that they are arithmetical problems.’
what is proposed here – is that a chess problem is
to be interpreted as an arithmetical
problem – and that is fair enough
however such an interpretation is just one of any
number of possible descriptions of the matter
e.g. what if the chess problem is seen as a problem
of strategy?
the point is that the interpretation – the description
– that we give a problem in chess – or for that matter a problem in any other
context – is open to question
there is no definite description
any description is open to question – open to doubt
– is uncertain
‘The following would be an example of an
arithmetical game: We write down a four-figure number at random, e.g. 7368; we
are to get to as near to this number as possible by multiplying the numbers 7,
3, 6, 8 with each other in any order. The players calculate with pencil and
paper, and the person who comes nearest to the number 7368 in the smallest
number of steps wins. (Many mathematical puzzles, incidentally, can be turned
into games.)’
arithmetic is a game – a rule governed sign game
a game can be the basis of other games –
games within games
‘Suppose a human being had been taught arithmetic
only for use in an arithmetical game: would he have learnt something different
from a person who learns arithmetic for its ordinary use? If he multiplies 21
by 8 in the game and gets 168, does he do something different from a person who
wanted to find out how many 21 x 8 is?’
would he have learnt something different?
if the game player’s description of what he does
when he plays the arithmetical game is different to the description of person who plays the arithmetical in its
ordinary use
then there is an argument for saying that what the
game player has learnt is different to the other player
it is all a question of description –
and any description – is open to question – open to
doubt – is uncertain
‘It will be said: the one wanted to find out the
truth, but the other did not want to do anything of the sort.’
yes – anything can be said –
as for the truth –
the truth is what you give your assent to – for whatever reason
when you play a game – you give your assent in playing it –
you give your assent to the rules – to the result –
when you do an arithmetical calculation – if you do
the calculation in accordance with the rules of the game – you get the outcome
that is determined by those rules –
again – the truth here – is what you assent to in
the performing of the calculation –
if you don’t assent
to the game – you don’t play it
yes you can question and doubt the rules of the
‘arithmetical game’ – or the rules for ‘ordinary use’ – that is not playing the game –
that is not doing
mathematics –
subjecting
the proposals – the rules of mathematics – to question and doubt – recognizing
them as uncertain –
is not mathematics – it is logic
‘Well we might want to compare this with a game
like tennis. In tennis the player makes a particular movement which causes the
ball to travel in a particular way, and we can view his hitting the ball either
as an experiment, leading to the discovery of a particular truth, or else as a
stroke with the sole purpose of winning the game.
But this comparison wouldn’t fit, because we don’t
regard a move in chess as an experiment (though that too we might do); we
regard it as a step in a calculation.’
where you play a game – with a competitor – yes the
rules of the game govern it’s activity –
however in any such game – you are constantly
facing the unknown –
that is – while there are rules – even so – you don’t know what your competitor will do
–
you don’t know what mastery you competitor has over
the rules –
and your competitor is in the same position of not
knowing in relation to you
here the rules of the game as it were define or map
out the domain of not-knowing –
and yes – when you play chess or tennis – or any
game – you do experiment with not-knowing –
in any experiment you face the unknown – fair and
square – and place a bet
as for calculating –
calculating in chess is a game within a game – a
game within the larger game
calculating without a competitor is simply a matter
of following rules –
yes – you can question those rules – but
questioning the rules of a calculation – is not calculating
questioning the rules of a game – is not playing the game
‘Someone might perhaps say: In the arithmetical
game we do indeed do the multiplication 21 x 8.
168
but the equation 21 x 8 = 168 doesn’t occur in the
game. But isn’t that a superficial distinction? And why shouldn’t we multiply
(and of course divide) in such a way that the equations were written down as
equations?’
the equation is just another formulation or
statement of the calculation
the equation may not occur in the game – but to
play the game we do the multiplication – which could be restated in the form of
the equation –
the point is that any proposal – and proposition –
in this case – a calculation – is open to question – open to doubt – in any
number of ways – including how it is formulated – how it is stated
‘why shouldn’t we multiply (and divide) in such a
way that the equations were written down as equations?’
no reason at all –
it is just that there is more than one way of
performing the propositional action
‘So one can only object that in the game the equation
is not a proposition. But what does that mean? How does it become a
proposition? What must be added to it to make it a proposition? – Isn’t it a
matter of the use of the equation (or of the multiplication)? – And it is
certainly a piece of mathematics when it is used in the transition from one
proposition to another. And thus the specific difference between mathematics
and a game gets linked up with the concept of proposition (not ‘mathematical
proposition’) and thereby loses its actuality for us.’
a proposition is a proposal –
open to question – open to doubt – uncertain
an equation is a proposal
and any equation is open to question – open to
doubt – uncertain
a proposal is a proposition – you could say whether
or how it is used –
isn’t it the case that a proposal put – is a proposal used – is a proposition in use?
a game is a proposal – is a proposition –
the game as a proposal – is open to question – open
to doubt – is uncertain
a game as
played is played without question
any proposition of mathematics is open to question
– open to doubt – is uncertain
mathematics as a game – is played – without question
a proposal – is
that which is put
and that which is put – is actual
‘(Here we may remind ourselves that in elementary
school they never work with inequations. The children are only asked to carry
out multiplications correctly and never – or hardly ever – asked to prove an
inequation.)’
the ‘unequals game’ is just as rule governed as the
equals game
‘When I work out 21 x 8 in our game the steps in
the calculation, at least, are the same as when I do it in order to solve a
practical problem (and we could make room in a game for inequations also). But
my attitude to the sum in other respects differs in the two cases.
Now the question is: can we say of someone playing
the game who reaches the position “21 x 8 = 168’ that he has found out that 21
x 8 = 168? What does he lack? I think the only thing missing is an application
for the sum.’
‘can we say .. that he has found out that 21 x 8 =168?’
–
it is not the only way to describe what has
happened but there is nothing wrong with
the description ‘found out’ –
you calculate – follow a rule to ‘find out’ – the
result –
that is the game you play
the game is complete in itself – there is nothing
lacking
yes – it can be played for an application –
it can also be played for the pure pleasure of the
exercise –
the pleasure of the game
‘Calling arithmetic a game is no more and no less
wrong than moving chessmen
according to chess-rules; for that might be a
calculation too.’
yes – moving chess men according to chess rules –
as with any action – can be described in any number of ways
‘So we should say: No, the word ‘arithmetic’ is not
the name of a game. (That too of course is trivial) – But the meaning of the
word “arithmetic” can be clarified by bringing out the relationship between
arithmetic and an arithmetical game, or between a chess problem and the game of
chess.
But in doing so it is essential to recognize that
the relationship is not the same as that between a tennis problem and the game
of tennis.
By ‘tennis problem” I mean something like the
problem of returning a ball in a particular direction in given circumstances.
(A billiard problem isn’t a mathematical problem (although its solution may be
an application of mathematics). A billiard problem is a physical problem and
therefore a “problem” in the sense of physics; a chess problem is a
mathematical problem and so a “problem” in a different sense, a mathematical
sense.’
a game is a rule governed propositional action
arithmetic is a game
‘tennis’ is a rule governed propositional action
involving two or more players
i.e. the next shot is a proposal
you would quite naturally describe it as a physical
game – however it – like any game can be variously described –
i.e. some commentators focus on the personalities
of the players
a billiard problem can be described as
physical –
there are of course other ways to describe the
game-
i.e. you might describe a problem in billiards in
terms of strategy –
or might describe the problem in historical terms –
how it has been dealt with in past games
a chess problem – can be described as mathematical –
but again this is just one possible description –
again – it could be described descried in terms of
strategy – personality – history etc.
any description of propositional action is open to
question – open to doubt – is logically speaking – uncertain
‘In the debate between “formalism” and “contentful
mathematics” what does each side assert? This dispute is so like the one
between realism and idealism in that it will soon have become obsolete, for
example, and in that both parties make unjust assertions at variance with their
day to day practice’
how a propositional activity is described is open
to interpretation –
and any interpretation – any description – is open
to question – open to doubt – is in so far as it is a proposal – uncertain
‘Arithmetic
isn’t a game, it wouldn’t occur to anyone to include arithmetic in a list of
games played by human beings’
wrong – it occurred to me
‘What constitutes winning and losing in a game (or
success in patience)? It isn’t of
course, just the winning position. A special rule
is needed to lay down who is the winner. (“Draughts” and “losing draughts”
differ only in this rule.)’
in a competition game – the winning position – is
the result of the game
a rule determining the winner is not I think a
special rule – it is a rule of the
game –
without such a rule – there is no game – so it is
integral to the game
success – in patience is rule governed
in patience – though you are not playing with a
competitor – you are playing against a rule governed indeterminacy – and with
the revelation of each card – you face uncertainty
the rule in almost all variants of draughts is that
the player without pieces remaining or who cannot move due to being blocked –
loses the game
‘losing draughts’ or ‘giveaway checkers’ is another
game –
in ‘losing draughts’ the rules are the same as
draughts but the aim is to lose all your pieces
‘Now is the rule which says “The one who first has
his pieces in the other half is the winner” a statement? How would it be
verified? How do I know if someone has won? Because he is pleased, or something
of the kind? Really what the rule says is: you must try to get some pieces as
soon as possible, etc.
In this form the rule connects the game with life.
And we could imagine that in an elementary school in which one of the subjects
taught was chess the teacher would react to a pupil’s bad moves in exactly the
same way as to a sum worked out wrongly.’
is the rule a statement – yes – the rule is a proposal – a proposition
how would it be verified?
the game is played – not verified
how do I know if someone has won?
I know if someone has won – if they have played so
as to satisfy the rule that determines the winner
‘In this form the rule connects the game with
life.’
if a teacher is trying to inculcate the rules of a
game – it matters little what the game is – the issue is the same
however I would put that teaching obedience to
rules is close to a waste of time
what we should be doing is showing the rules to
pupils – explaining why we have them –
and getting them to think about the value of rules
– even to question them in a thoughtful manner
people learn games not just by mastering rules –
but rather by learning to think within rules –
and thinking here is the logical activity of
question and doubt –
to think is to recognise – appreciate – and operate
– with and in –
uncertainty –
this is the game of life
‘I would like to say: It is true that in the game
there isn’t any “true” and “false” but then in arithmetic there isn’t any
“winning” and “losing”.’
that is correct as far as it goes –
however Wittgenstein’s statement here draws a
distinction between the ‘game’ and ‘arithmetic’ –
when in fact – arithmetic is a game –
that is to say a rule governed proposition activity
and in fact there isn’t any ‘true’ or ‘false’ in
the arithmetic game –
you play that game in accordance with the its rules
–
if you don’t play the arithmetic game in accordance
with its rules –
it is not that you play a ‘false’ game – or the result of your calculation is
‘false’ –
it is rather that you don’t play the game –
when you calculate – it is not that you can
‘miscalculate’ – or ‘make a mistake’ – or get it ‘wrong’ –
if you don’t follow the rules – you don’t calculate
a true proposal – a true proposition – is one you assent to – for whatever reason
a false proposal – a false proposition – is one you
dissent from – for whatever reason
if you play the game – you assent to it –
if you don’t play it properly –
you don’t play it
‘I once said that it was imaginable that wars might
be fought on a kind of chessboard according to the rules of chess. But if
everything really went simply according to the rules of chess, then you
wouldn’t need a battlefield for war, it could be played on an ordinary board;
and then it wouldn’t be a war in the ordinary sense. But you really could
imagine a battle conducted in accordance with the rules of chess – if say, the
“bishop” could fight with the “queen” only when his position in relation to her
was such that he could be allowed to ‘take’ her in chess.’.
yes – chess as a propositional model for a rule
governed war
how likely though in reality – when war in fact
just is the result of the breakdown of rule governed behaviour?
so called ‘rules of war’ I think you will find are
irrelevant to actual war
and I would suspect – most likely proposed by those
who don’t do any actual fighting
‘Could we imagine a game of chess being played
(i.e. a complete set of chess moves being carried out) in such different
surroundings that what happened wasn’t something we could call the playing of a
game?
Certainly, it might be a case of the two
practitioners collaborating to solve a problem. (And we could easily construct
a case on these lines in which such a task would have a utility).’
if the activity is rule governed – and it is played in accordance with the rules – it
is a game
collaborating to solve a problem within a game –
might just be figuring out which rule does apply in the circumstance in
question
and where the problem is not a chess problem per
se – if the model that is being used to deal with the problem – is a rule
governed propositional model – then the question will be – which rule applies?
‘The rule about winning and losing really just
makes a distinction between two poles. It is not concerned with what happens to
the winner (or the loser) – whether, for instance, the loser has to pay
anything.
(And similarly, the thought occurs, with “right” or
“wrong” in sums.)’
it is a question of description
if you describe how the game works – the ‘logic’ of the game – independently of the players –
then ‘winning’ and ‘losing’ – will not be part of that description
if on the other hand you describe the play – then ‘winning’ and ‘losing’
will be part of the description
as to arithmetic –
you play
that game – if you play it according to its rules –
‘right’ – is irrelevant
if you don’t play it according to the rules – you don’t play it – and in that case –
‘wrong’ – has no place
‘In logic the same thing keeps happening as
happened in the dispute about the nature of definition. If someone says that a
definition is concerned only with signs and does no more than substitute one
sign for another, people resist and say that that isn’t all a definition does,
or there are many different kinds of definition and the interesting and
important ones aren’t the mere “verbal definitions”.
They think, that is, that if you make definition
out to be a mere substitution rule for signs you take away its significance and
importance. But the significance of definition lies in its application, and its
importance for life. The same thing is happening to day in the dispute between
formalism and intuitionism etc. People cannot separate the importance, the
consequences, the application of a fact from the fact itself; they can’t
separate the description of the thing from its importance.’
yes we define – to make known – and any definition
– and any propositional knowledge – is
open to question –
and yes we use definitions –
and any use of a definition – any application –
like the definition itself – is open to question – open to doubt – is uncertain
we operate with uncertainty – in uncertainty – that
is our life – from a logical point of view
‘they can’t separate the description of the thing
from its importance.’ –
the ‘thing’ in the absence of description is unknown
description makes known –
and any ‘description’ – is open to question – open
to doubt – is uncertain
the importance of the thing – is the importance of
the description
and ‘importance’ is a rhetorical issue
‘We are always being told that a mathematician
works by instinct (or that he doesn’t proceed mechanically like a chess player
or the like), but we aren’t told what that’s supposed to have to do with the
nature of mathematics. If such a psychological phenomenon does play a part in
mathematics we need to know how far we can speak about mathematics with
complete exactitude, and how far we can only speak with the indeterminacy we
must use in speaking of instincts.’
there are any number of possible descriptions of
mathematical behaviour –
‘how far can we speak of mathematics with complete
exactitude?’
how far can we speak of anything with complete exactitude?
any proposal – any proposition we put forward – be
it ‘mathematical’ – or otherwise –
is logically speaking – open to question – open to
doubt – is uncertain –
‘exactitude’ or even better – ‘complete
exactitude’(?) – is rhetorical rubbish
as for ‘instincts’ –
to say ‘a mathematician works by instinct’ – is to
propose an ‘explanation’ of his behaviour
now any explanation – as with any description – is
open to question – open to doubt –
is uncertain
nevertheless – if in a certain context – it proves
useful – then it has value –
the reality is that the mathematician – as with
everyone else – does not have an
explanation of his behaviour – an explanation – that is beyond question
– beyond doubt – that is certain –
still we use explanations – and in general we run
with what is at hand – whatever is the fashion
intuition has proved an enduring fashion for the
mathematician –
I frankly don’t think it matters an iota whether
the mathematician can explain – can account for what he does –
what matters is that he does – what does –
‘explanation’ – is always – after the fact –
it’s just packaging –
and I suppose we all prefer the gift wrapped
‘Time and again I would like to say: What I check is the account books of mathematics; their mental process, joys,
depressions and instincts as they go about their business may be important in
other connections, but they are no concern of mine.’
nor of mine
12. There is
no meta mathematics
‘No calculus can decide a philosophical problem.
A calculus cannot give us information about the
foundations of mathematics.’
‘No calculus can decide a philosophical problem’?
a calculus is game – a sign game
a philosophical problem – is a proposal – subjected
to question – to doubt –
a calculus – a sign game – in fact any ‘game’ – as
played – is played – without question
if questioned – if doubted – then the ‘game’ – is
not being played – it is being proposed
and any proposal – any proposition – is open to
question – open to doubt – is uncertain
philosophical problems – that is – propositions
questioned – are not – logically speaking ‘decided’ in any final sense
any decision taken – is open to question – open to
doubt – uncertain
a game is not a propositional decision in response
to question – to doubt – to uncertainty–
a game is a propositional application
‘A calculus cannot give us information about the
foundations of mathematics’?
the foundations of mathematics?
the foundations of mathematical proposals –
propositions –
a proposal – a proposition – however described – in
whatever contexts it is used –
is open to question – open to doubt – is uncertain
the logical ‘foundation’ of the proposal – of the
proposition – is uncertainty –
is ‘uncertainty’ a foundation?
I think it best to speak of the proposal – the
proposition – as foundationless.
‘So there can’t be any “leading problems” of
mathematical logic, if those are supposed to be problems whose solution would
at long last give us the right to do arithmetic as we do.’
in the words of Bentham – talk of ‘rights’ is
nonsense on stilts – rhetorical rubbish –
and that’s all we have here
arithmetic is a sign game – a calculation game – a
propositional game –
a game developed over centuries – a game played
because it is useful
‘We can’t wait for the lucky chance of the solution
of a mathematical problem.’
what does he mean here?
‘a mathematical problem’ – is what?
a problem
emerges when there are different interpretations of a rule – or a question
about what rules apply –
a ‘problem’ if you like – is the question – ‘how to proceed?’ –
any such questioning – is logical –
in a mathematical context – such questioning is
logical
so on this view there are no mathematical problems
as such
any problem per
se is logical
in a mathematical context – the logical question
might be which mathematical game –
which sign game – which calculation – to use?
as for ‘lucky chance’ –
there are games – rules to games – games played in
accordance with rules –
there is no chance – no luck
you play the game or you don’t
‘I said earlier “calculus is not a mathematical
concept”; in other words, the word “calculus” is not a chess piece that belongs
to mathematics.
There is no need for it to occur in mathematics. –
If it is used in a calculus nonetheless, that doesn’t make the calculus into a
meta calculus; in such a case the word is just a chessman like all the others.’
‘calculus’ – as with any word – any proposal – is
open to question – open to interpretation
it occurs in mathematics
a meta calculus?
would be a calculus that explains the calculus in use –
a meta theory of calculus – is more likely
that is an account – a theory of – the calculus in use
and any such proposal – like the calculus – it purports to
explain – will be open to question – open to doubt – is uncertain
‘Logic isn’t meta mathematics either; that is work
within logical calculus can’t bring to light essential truths about
mathematics. Cf. here the “decision problem” and similar problems in modern
mathematical logic.’
the point is that meta mathematics is no more than
a proposal to account for – to explain – to underwrite mathematics
a calculus is a propositional operation
there are no essential truths
any proposal – any decision –
is open to question – open to doubt – is uncertain
regarding mathematics in this light –
is to regard it logically
‘(Through Russell and Whitehead, especially
Whitehead, there entered philosophy a false exactitude that is the worst enemy
of real exactitude. At the bottom of this there lies the erroneous opinion that
a calculus could be the foundation of mathematics.)’
there is no foundation to mathematics
any propositional activity – mathematics included –
is open to question – open to doubt – is uncertain
quite apart from the logic of the matter – the
history of mathematics demonstrates – that its concepts – its terms – its
operations – its propositions – have been developed out of question – out of
doubt – out of uncertainty
any concept of exactitude – is uncertain
as for a calculus as the foundation of mathematics
–
this – or any other proposal of foundation – cannot
be taken seriously
what you have in any such proposal – is the desire
for foundation – nothing more –
and it is a desire based on a corruption of
propositional logic
‘Number is not at all a “fundamental mathematical
concept”.
There are so many calculations in which numbers
aren’t mentioned.
So far as concerns arithmetic, what we are willing
to call numbers is more or less arbitrary. For the rest, what we have to do is
to describe the calculus – say of cardinal numbers – that is, we must give its
rules and by doing so we lay foundations of arithmetic.’
if by ‘fundamental’ – is meant that which is beyond
question – beyond doubt –
a certainty –
then logically speaking there is no fundamental in
any propositional context
numbers are signs – in sign games
a sign is a proposal – open to question – open to
doubt – uncertain
mathematics is the language of sign games
its foundation – is utility
‘Teach it to us and then you have laid its
foundations’
yes – it ‘foundation’ – is use
‘(Hilbert sets up rules of a particular calculus as
the rules of meta mathematics.)’
the rules of a
calculus – as the rules (of an
account) of mathematics?
the question is – how could you know that one set
of rules – applies to all expressions of mathematics?
at best you have a conjecture
mathematics will be described – accounted for – in
various ways – at various times – by various people – to various ends
yes we will have these descriptions – these meta
mathematics proposals –
but this descriptive activity – is not mathematics
‘A system’s being based on first principles is not the same as its being developed
from them. It makes a difference whether it is like a house resting on its
lower walls or like a celestial body floating in free space which we have begun
to build beneath although we might have built anywhere else.’
first principles – are just descriptions of
starting points –
there will always be a question as to whether where
you start is wise
this question is always live – at any stage of the
activity –
any starting place – as with any action from that
starting place – and indeed any assessment of the result of any action – is at
any time – open to question – open to doubt – uncertain
yes – it will make a difference how you go about
your enterprise – how you envisage the project – where you start – how you
approach the construction
‘Logic and mathematics are not based on axioms, any
more than a group is based on the elements and operations that define it. The
idea that they are involves the error of treating the intuitiveness, the
self-evidence, of the fundamental propositions as a criterion for correctness.
A foundation that stands on nothing is a bad
foundation.’
logic and mathematics are propositional activities
a proposition is a proposal – open to question –
open to doubt – uncertain
any proposal put forward to ‘explain’ a
propositional activity – is itself –
open to question – open to doubt – uncertain
axioms are proposals
intuitiveness – is a proposal to account for
certain propositional behaviour
any proposal – is evidence of itself
the ‘fundamental propositions’ – at best are
starting blocks
a criterion for correctness – is whatever you decide it is – in whatever
context requires it
any so called ‘foundation’ is a rhetorical device
rhetoric stands on deception
there is no foundation to the proposition
the proposition stands on nothing
‘(p.q) v (p.
- q) v (- p.q) v ( - p. – q.) : That is my tautology, and then I go on to say that
every “proposition of logic” can be brought into this form in accordance with
specified rules. But that means the same as: can be derived from it. This would
take us as far as the Russellian method of demonstration and all we add to it
is that this initial form is not itself an independent proposition, and that
like all “laws of logic” it has the property that p, p v Log = Log.’
the tautology is a game – a game-proposition –
a propositional game – played according to rules –
and yes – you can extend the game to every
proposition of logic
the game can be played as a derivation game – then
yes – it means the same as – ‘can be derived from it’
any proposal – any proposition as put – is independent
a proposition can
be represented as dependent i.e. – ‘explained’ – accounted for – in terms
of other proposals
proposals – propositions – open to question – open
to doubt – uncertain
‘It is indeed the essence of a logical law that
when it is conjoined with any proposition it yields that proposition. We might
even begin with Russsell’s calculus with definitions like
p É p
: q. = .q
p : p v
q. = .p, etc.’
yes you can take what is proposed – what is
presented – what is given – and reconfigure it into a word-game – a sign-game –
any such representation – will come with an
interpretation –
and any interpretation is open to question – open
to doubt – is uncertain
13. Proofs of
relevance
‘If we prove that a problem can be solved, the
concept “solution” must occur somewhere in the proof. (There must be something
in the mechanism corresponding to the concept.) But the concept cannot have an
external description as its proxy; it must be genuinely spelt out.’
the solution to a problem – will be a proposal – open to
question – open to doubt – uncertain –
the so called ‘proof’ – is the argument to the ‘solution’ –
to the proposal
the argument to the ‘solution’ – the so called ‘proof’ – as
with the solution – is open to question – open to doubt – is uncertain
‘The only proof of the
provability of a proposition is a proof of the proposition itself.’
the
‘provability’ of a proposition – is the argument for the proposition
as for the
proof of the provability – that would be – the argument for the argument for
the proposition
does the
argument for a proposition – need argument itself?
perhaps –
but all
this would mean is that we have is a complex of arguments –
all of
which are open to question – open to doubt – uncertain
‘But there is something we
might call a proof of relevance: an example would be a proof convincing me that
I can verify the equation 17 x 38 = 456 before I have actually done so. Well
how is it that I know that I can check 17 x 34 = 456, whereas I perhaps
wouldn’t know, merely by looking, whether I could check an expression in the
integral calculus? Obviously it is because I know the equation is constructed
in accordance with a definite rule and because I know the kind of connection
between the rule for the solution of the sum and the way in which the sum is
put together. In that case a proof of relevance would be something like a
formulation of the general method of doing things like multiplication sums,
enabling us to recognize the general form of the proposition it makes it
possible to check. In that case I can say I recognize that this method will
verify the equation without having actually carried out the verification.’
‘In that case a proof of relevance would be
something like a formulation of the general method of doing things like
multiplication sums, enabling us to recognize the general form of the
proposition it makes it possible to check.’
this so called ‘proof of
relevance’ then –
is nothing more than –
recognizing a propositional
game –
and knowing how it is
played
‘When we speak of proofs of
relevance (and other similar mathematical entities) it always looks as if in
addition to the particular series of operations called proofs of relevance, we
had a quite definitive inclusive concept of such proofs or of mathematical
proofs in general; but in fact the word is applied with many different, more or
less related, meanings. (Like words such as “king”, “religion”, etc; cf
Spengler.) Just think of the role of examples in the explanation of such words.
If I want to explain what I mean by “proof”, I will have to point to examples
of proofs, just as when explaining the word “apple” I point to apples. The
definition of the word
“proof” is in the same case
as the definition of the word “number”. I can define the expression “cardinal
number” by pointing to examples of cardinal numbers: indeed instead of the
expression I can actually use the sign “1, 2, 3, 4, and so on ad infin”. I can
define the word number too by pointing to various kinds of number; but when I
do so I am not circumscribing the concept of “number” as definitely as I
previously circumscribed the concept cardinal number, unless I want to say it
is only the things at present called numbers that constitute the concept
“number”, in which case we can’t say of any new construction that it constructs
a kind of number. But the way we want to use the word “proof” in is one in
which it isn’t simply defined by a disjunction of proofs currently in use; we
want to use it in cases of which at present we “can’t have any idea”. To the
extent that the concept of proof is sharply
circumscribed, it is only through particular proofs, or series of proofs (like
the number series), and we must keep that in mind if we want to speak
absolutely precisely about proofs of relevance, of consistency etc.’
yes – ‘proof’ as with any
word – any concept – is open to question – open to doubt – is uncertain
the issue is use – where
and how we use the term
to suggest that there is a
use for the term ‘in cases of which at present we “can’t have any idea” –
is really to suggest that
there is a meaning to proof regardless of actual use
what are we to call this?
a mystical proof?
‘We can say: a proof of
relevance alters the calculus containing the proposition to which it refers. It
cannot justify a calculus containing
the proposition, in the sense in which carrying out the multiplication 17 x 23
justifies the writing down of the equation 17 x 23 = 391. Not, that is, unless
we expressly give the word “justify” that meaning. But in that case we mustn’t
believe that if mathematics lacks this justification, it is some sense more
general and widely established sense illegitimate or suspicious. (That would be
like someone wanting to say: “the use of the expression ‘pile of stones’ is
fundamentally illegitimate, until we have laid down officially how many stones
make a pile” but it wouldn’t “justify” it in any generally recognized sense;
and if such an official definition were given, it wouldn’t mean that the use
earlier made of the word would be stigmatized as incorrect.)’
17 x 23 = 391 – is a rule
governed propositional game
a game is played –
played according to its rules
a game is played – not justified
there is no ‘proof of
relevance’ – there is just the game – its rules and its play
the expression ‘pile of
stones’ – is not a rule governed propositional game –
it is a proposal
there is no question of
‘justifying’ a proposal or justifying a propositional use
a proposal – is open to
question – is open to doubt – is uncertain

‘The proof of the
verifiability of 17x 23 = 391 is not a “proof” in the same sense of the word as
the proof of the equation itself. (A cobbler heels, a doctor heals: both …) We
grasp the verifiability of the equation from its proof somewhat as we grasp the
verifiability of the proposition “the points A and B are not separated by a
turn of the spiral” from the figure. And we see that the proposition stating
verifiability isn’t a “proposition” in the same sense as the one whose
verifiability is asserted. Here again, one can only say: look at the proof, and
you will see what is proved here,
what gets called “the proposition proved”.’
the so called ‘proof of the
verifiability of 17 x 23 = 391’ – just is the arithmetical game – 17 x
23 = 391
the game and its rules of
play
a propositional game is not
verified – it is played
look at the game – and
you’ll see the play –
what gets played is the
game
‘Can one say that at each
step of a proof we need a new insight? (The individuality of numbers.)
Something of the following sort: if I am given a general (variable) rule, I
must recognize each time afresh that this rule may be applied here too (that it holds for this case
too). No act of foresight can absolve me from this act of insight. Since the form in which the rule is applied is in fact a
new one each at every step. But it is not a matter of an act of insight, but of an act of decision.’
‘Can one say that at each
step of a proof we need a new insight?
it is not a question of
insight – insight is mysticism
here the issue is the
application of the rule
and yes questions can be
asked
and to proceed
mathematically –
decisions have to be made
‘What I call a proof of relevance
does not climb the ladder to its proposition – since that requires that you
pass every rung – but only shows that the ladder leads in the direction of that
proposition. (There are no surrogates in logic). Neither is an arrow that
points the direction a surrogate for going through all the stages towards a
particular goal.’
if you understand that
mathematics is a network of propositional games –
rule governed propositional
actions –
yes – you might in a ‘meta-
moment’ – inquire into the history and so called provenance of a game – of the
rules
but the mathematical issue
is – the game and the playing of the game –
and the question is – are
you a player?
if so – you follow the
rules – you play the game
14. Consistency Proofs
‘Mathematicians nowadays
make so much fuss about proofs of consistency of axioms. I have the feeling
that if there were a contradiction in the axioms of a system it wouldn’t be
such a great misfortune. Nothing easier than to remove it.’
yes –
but
consistency does indicate order in your propositional action
and the
value of the contradiction is that it brings undisciplined thinking to a stop
‘Suppose someone wanted to
add to the usual axioms of arithmetic the equation 2 x 2 = 5. Of course that
would mean that the sign of equality had changed its meaning, i.e. that there
would now be different rules for the equals-sign.’
no – the sign of equality
hasn’t changed its meaning –
what you have is a new
equals game
2 x 2 = 5 – would not be accepted
as an axiom of arithmetic unless it was decide that all other relevant axioms
be made consistent with it –
this would be a very
disruptive action – hard to see how there could be any advantage in such a
change
‘If I inferred “I cannot
use it as a substitution sign” that would mean that its grammar no loner fitted
the grammar of the word “substitute” (“substitution sign”, etc.) For the word
“can” in that proposition doesn’t indicate a physical (physiological,
psychological possibility.’
yes
‘“The rules may not
contradict each other” is like “negation, when doubled, may not yield a
negation”. That is, it is a part of the grammar of the word “rule” that if “p”
is a rule, “p. –p” is not a rule.’
That means we could also
say: the rules may contradict each other, if the rules for the use of the word
“rule” are different – if the word “rule” has different meanings.’
yes – it’s
really a question of propositional practice –
and that
always involves decision – and the acceptance or rejection of any decision by
those engaged in the practice
‘Here too we cannot give
any foundation (except a biological or historical one or something of the
kind); all we can do is to establish agreement, or disagreement between rules
for certain words, and say that those words are used with these rules.’
yes –
exactly
‘It cannot be shown, proved
that these rules can be used as the rules of this activity.
Except be showing that the
grammar of the description of the activity fits the rules.’
again – the
question of practice – what works – what doesn’t – what’s accepted – what is
not accepted
a
correlation of grammars – is a good start.
‘“In rules there mustn’t be
a contradiction” looks like an instruction: “In a clock the hand mustn’t be
loose on the shaft.” We expect a reason: because otherwise … But in the first
case the reason would have to be: because otherwise it wouldn’t be a set of
rules. Once again we have a grammatical structure that cannot be given as a
logical
foundation.’
yes – we
have grammatical practice
as to logical
foundation –
any
proposal – be a game proposal or not – logically speaking is open to question –
open to doubt – is uncertain
the point
of logic – is that there is no foundation to propositional action
‘In the indirect proof that
a straight line can have only one continuation
through a certain point we make the supposition that a straight line could have
two continuations. – If we make that supposition, then the supposition must
make sense. – But what does it mean to make that supposition? It isn’t making a
supposition that goes against natural history, like the supposition that a lion
has two tails. – It isn’t making a supposition that goes against an ascertained
fact. What it means is supposing a rule; and there’s nothing against that
except that it contradicts another rule, and for that reason I drop it.
Suppose that in the proof
there occurs the following drawing

to represent a straight
line bifurcating. There is nothing absurd (contradictory) in that unless we
have some stipulation that it contradicts.’
‘that a straight line can have only one continuation’ –
you could well ask – really
is there any need for such a definition?
if you have definition of
‘straight line’ – does the phrase ‘can only have one continuation’ – in anyway
add to the definition?
i.e. isn’t ‘can only have
one continuation’ – contained in the definition?
as for Wittgenstein’s
drawing – yes he has made the point that a straight line – can a have more than
one continuation
ok – but does the
bifurcated line – fit the definition of straight line?
or if the focus is on the
bifurcated line – don’t we have to change our definition of straight line?
no big deal really –
it is just a matter of
being clear about what it is you are proposing –
‘Suppose that in the proof
there occurs a drawing to represent a straight line bifurcating. There is
nothing absurd (contradictory) in that unless we have some stipulation that it
contradicts.’
yes
‘If a contradiction is
found later on, that means that hitherto the rules have not been clear and
unambiguous. So the contraction doesn’t matter, because we can now get rid of
it by enunciating a rule.’
if a contradiction is found
later on – you would say the propositional action was not properly conceived –
sloppy work –
there is a rule against
that
‘In a system with a clearly
set out grammar there are no hidden contradictions, because such a systems must
include the rule which makes the contradiction discernable. A contradiction can
only be hidden in the sense that it is in the higgledy-piggledy zone of the
rules, in an unorganized part of the grammar; and there it doesn’t matter since
it can be removed by organizing the grammar.’
yes
‘Why may not the rules
contradict one another? Because otherwise the wouldn’t be rules.’
it is not
there wouldn’t be rules –
the point
is there would be no game
15. Justifying arithmetic and preparing it for applications (Ramsey,
Russell)
‘One always has an aversion
to giving arithmetic a foundation by saying something about it’s application.
It appears firmly grounded in itself. And that derives from the fact that
arithmetic is its own application.’
arithmetic is a propositional game –
any proposal – any proposition – is open to question – open
to doubt – is uncertain –
if a ‘foundation’ is that which is – not open to question –
not open to doubt – is that which is certain –
there is no foundation – to the proposition
certainty is ignorance – is prejudice
the propositions of arithmetic – as with any proposition –
however described or classified – are open to question – open to doubt
arithmetic is a propositional game –
a game is played – and played in accordance with its rules
–
any ‘rules’ here are simply agreed propositions – agreed
propositional practices
the game as played
– is played without question – without doubt
if you approach the propositions that make up a game – from
a logical point of view –
that is if you put them to question – to doubt – recognize
their uncertainty – you are not playing
the game
if you put the propositions of arithmetic to question – you
are not doing arithmetic –
your activity is logic
‘it appears firmly grounded in itself’ – is to say
that as played – the arithmetic game
– is played without question –
this is true of any game
‘arithmetic is its own application’?
a game – is its play
that the idea of a game – any game – is that it be played
the arithmetic game – is a play
‘You could say: why bother to limit the application
of arithmetic, that takes care of itself. (I can make a knife without bothering
about what kinds of materials I will have cut with it; that will show soon
enough.)
What speaks against our demarcating a region of
application is the feeling that we can understand arithmetic without having any
such region in mind. Or put it like this: our instinct rebels against anything
that isn’t restricted to an analysis of the thoughts already before us.’
as to the question of the limits of the application
of arithmetic –
it is like asking – what are the limits of play?
you play when you play
and furthermore there are no limits to the making
of games –
new games – or modifications or developments of
older games can be proposed – at any time for any reason
their significance in any game playing arena will
be decided by the game players
it is not a question of ‘the analysis of the
thoughts already before us’ –
what is ‘before us’ – is the game – you play it –
or you don’t –
you need to understand the rules – but the game
itself is an explanation of its rules –
and how do we learn arithmetic? –
a player shows us how the game is played
‘You could say arithmetic is a kind of geometry; i.e. what
in geometry are constructions on paper in arithmetic are calculations (on
paper). You could say it is a more general kind of geometry.’
in geometry proposals are put – propositions are put –
and yes geometry can be seen as a game – a spatial game – a
construction game
arithmetic ‘a more general kind of geometry’?
what does ‘more general’ mean here?
that when you do arithmetic – you are actually doing
geometry – that geometry is just another form of arithmetic – that without
arithmetic – there would be no geometry?
isn’t it rather the case that arithmetic and geometry are
different games –
different
propositional games – but different propositional games that complement each other?
‘It is always a question of whether and how far it’s
possible to represent the most general form of the application of arithmetic.
And here the strange thing is that in a certain sense it doesn’t seem to be
needed. And if in fact it isn’t needed, then it’s also impossible.’
arithmetic is a propositional game
the application of arithmetic – that is the play of the game
is the representation of the game –
in whatever context the game is played
‘The general form of its application seems to be represented
by the fact that nothing is said about it. (And if that’s a possible
representation, then it is also the right
one.)
nothing is
said about it – because there is no ‘general form of its application’ –
arithmetical
propositions are used where they are used – arithmetical games are played where
they are played
propositional
application is not ‘general’ –
it is
specific
‘The point of the remark that arithmetic is a kind of
geometry is simply that arithmetical constructions are autonomous like
geometrical ones and hence so to speak themselves guarantee their
applicability.
For it must be possible to say of geometry too that it is
its own application.’
arithmetic applies – where it is applied
geometry is applies – where it is applied
‘(In the sense in which we can speak of lines which are
possible and lines which are actually drawn we can also speak of possible
numbers.)’
as soon as you propose
a ‘possible number’ – the number is
proposed – it is there –
and then the issue is – just what is the point of this
proposal – this possible number – why the proposal – what does it do –
what is its use?
and of course the question is – how does this proposal stand
in relation to practised mathematics – number theory – as we know it?
proposing ‘a possible number’ is really no different to any
other proposal – in any other context –
the proposal is
open to question – open to doubt – is uncertain –
it is propositional uncertainty – that just is the source of
possibility

‘That is an arithmetical construction, and in a
somewhat extended sense also a geometrical one.’
what ‘that’ is –
is open to question – open to doubt – uncertain
we have a series of marks –
‘a series of marks’ – you could say is a basic
description – a starting point for further description
and as with any description – any proposal –
it is open to further description – and so on –
so the bottom line here is –
you run with whatever description suits your
purpose
‘Suppose I wish to use this calculation to solve
the following problem: if I have 11 apples and want to share them among some
people in such a way that each is given 3 apples how many people can there be?
The calculation supplies me with the answer 3. Now suppose I was to go through
the whole process of sharing and at the end 4 people had 3 apples in their
hands. Would I then say that the computation gave me the result? Of course not.
And that of course means that the computation was not an experiment.
It might look as though the mathematical
computation entitled us to make a prediction, say, that I could give three
people their share and there will be two apples left over. But that isn’t so.
What justifies us in making this prediction is an hypothesis of physics, which
lies outside the calculation. The calculation is only a study of logical forms,
of structures, and of itself cannot yield anything new.’
true – the computation is not an experiment
the computation is a propositional game – a game of
signs
three people with two apples over?
however the units of the computation are described
– apples – numbers – whatever –
the logical game is the same
‘If 3 strokes on the paper are the sign for the
number 3, then you can say the number 3 is to be applied in our language in the
way in which the three strokes can be applied.’
well yes – in those circumstances – those
propositional contexts – where three strokes on paper – represent ‘3’ –
however in another propositional context – where we
have an entirely different interpretation of three strokes on paper – i.e. – in
an artistic proposal –
this proposed equivalence of signs will not be in
play –
will for all intents and purposes – in this
different context – be of no significance
equivalence of signs – will be context dependent
and yes you can mix contexts – but that is just an
idle intellectual exercise – which might be an entertaining game for some – but it will have no functional value for
the contexts in question
the point is any ‘mark’ –
any marking – is only a sign – when given propositional interpretation
in the absence of
interpretation – a mark – logically
speaking – does not signify
it is an unknown –
which is to say it is a logical place for interpretation –
for propositional action
‘I said “One difficulty in the Fregean theory is
the generality of the words “concept’ and ‘Object’. For, even if you can count
tables, tones, vibrations and thoughts, it is difficult to bracket them all
together.” But what does “you can count them” mean? What it means is that it makes sense to apply the cardinal
numbers to them. But if we know that, if we know these grammatical rules, why
do we need to rack our brains about the other grammatical rules when we are
only concerned to justify the application of cardinal arithmetic? It isn’t
difficult “to bracket them all together”; so far as is necessary for the
present purpose they are already bracketed together.’
bracketing them all together? – finding a common
description –
but what does that have to do with the action of
counting?
it is not what is counted that is relevant here –
it is that a count takes place –
how you describe what is counted – is irrelevant –
and in fact – what is counted (however described) –
is irrelevant
counting is a rule governed action – the rule governed manipulation of numbers
a logical game –
numbers – cardinal numbers – are in the end –
simply tokens – logical tokens – for
the game – the game of counting –
tokens that enable the game to be played –
tokens for the action of the game
how you ‘cash in’ the logical tokens – is
irrelevant to the playing of the game
there is no question of ‘justifying’ the use of
numbers – of logical tokens
if you play the counting game – you use tokens –
that is the game
‘But (as we all know well) arithmetic isn’t at all
concerned about this application.
It’s applicability takes care of itself.’
the point is we play the game – where we play the game
the world – is just setting for the game
the world’s regions – contexts – if you will – are
just descriptive settings for the game
the game is played – and the arithmetic game is powerful just
because – as a logical game – it has no description – yet – just because it has
no description – it is open to description –
and just where
it is played can be the source of its description
yes I am counting – but right know – my context is
apples –
so the description I use – is ‘counting apples’
‘Hence so far as the foundations of arithmetic are
concerned all the anxious searching for distinctions between subject-predicate
forms, and contrasting functions ‘in extension’ (Ramsey) is a waste of time.’
analysis of subject-predicate forms and contrasting
functions in extension –
has no relevance at all to understanding the nature
of arithmetic –
to understanding the nature of the game – to understanding the action of the game –
as to foundations –
speculation on the basis of arithmetic – on the
‘foundations’ of arithmetic – is all very well –
but mathematics gets on quite well without it
the proposition is a proposal – open to question –
open to doubt – uncertain
any proposal for ‘foundation’ – is open to question
– open to doubt – is uncertain
any claim that a foundation is not open to question
– not open to doubt – is certain –
is illogical –
such claims are baseless and only have rhetorical
value –
that is if you think rhetoric has value
‘The equation 4 apples + 4 apples = 8 apples is a
substitution rule which I use if instead of substituting the sign “8” for the
sign “4 + 4”, I substitute “8 apples” for the sign “4 + 4 apples.
But we must be aware of thinking that “4 apples + 4
apples = 8 apples” is the concrete equation and 4 + 4 = 8 is the abstract
proposition of which the former is only a special case, so that the arithmetic
of apples, though much less general than the truly general arithmetic, is valid
in its own restricted domain (for apples). There isn’t any “arithmetic of
apples”, because the equation 4 apples + 4 apples = 8 apples is not a
proposition about apples. We may say that in this equation the word “apples”
has no reference. (And we can always say this about a sign in a rule which
helps to determine its meaning.)’
yes – here we have an arithmetical game – applied
to apples
‘How can we make preparation for something that may
happen to exist – in the sense in which Russell and Ramsey always wanted to do
this. We get logic ready for the existence of many placed relations, or for the
existence of an infinite number of objects, or the like.
Well we can make preparations for the existence of
a thing: e.g. I may make a casket for jewellery which may be made some time or
another – But in this case I can say what the situation must be – what the
situation is – for which I am preparing. It is no more difficult to describe
the situation now than after it has already occurred; even, if
it never occurs at all. (Solution of mathematical
problems). But what Russell and Ramsey are making preparations for is a
possible grammar.’
grammar is an account of – a theory of – language
use –
it is an explanatory proposal in relation to
language use
any theory of language use – is after the fact – the fact of the usage –
you need a language use – a language practise
before you have ‘an account of it’ –
a theory of it – a grammar of it
what we deal with in propositional logic – is what is proposed
as to what might be proposed – unless it is proposed –
it doesn’t exist – it’s not there
preparations for a possible grammar?
just strikes me as moving into a realm of logical
fiction.
‘On the one hand we think that the nature of the
functions and of the arguments that are counted in mathematics is part of its
business. But we don’t want to let ourselves be tied down to the functions now
known to us, and we don’t know if people will ever discover a function with 100
argument places; and so we have to make preparations and construct a function
to get everything ready for a 100 place-relation in case one turns up. – But
what does “a 100-place relation turns up (or exists)” mean at all? What concept
do we have of one? Or a 2-place relation for that matter? – As an example of a
2-place relation we give something like the relation between a father and son.
But what is the significance of this example for the further logical treatment
of 2-place relations? Instead of “aRb” are we now to imagine “a is the father
of b”? – If not, is this example or any example essential? Doesn’t this example
have the same role as an example in arithmetic, when I use 3 rows of 6 apples
to explain 3 x 6 = 18 to somebody?
Here it is a matter of our concept of application. – we have an image of an
engine which first runs idle, and then works a machine?
But what does application add to the calculation?
Does it introduce a new calculus? In that case it isn’t any longer the same calculation. Or does it give
substance in some sense which is essential to mathematics (logic)? If so, how
can we abstract from the application at all, even temporarily?
No, calculation with apples is essentially the same
calculation with lines or numbers. A machine is an extension of an engine, an
application is not in the same sense an extension of a calculation.’
‘But what does “a 100-place relation turns up (or
exists)” mean at all?
look – the idea of a 100 place relation can be proposed
–
does it have an application?
well that needs to be proposed too
I see no problem with imaginative mathematics
what we are talking about here is game proposal and
possibly construction
such might lead nowhere or it might be of use
the significance and value of any proposal – is
always live
however the idea that we can complete our
understanding of reality –
by covering all possibilities in some propositional
format –
is quite simply ridiculous
those philosopher and logicians who have gone down
this path –
have only demonstrated their ignorance –
of propositional logic – of propositional reality
they are clowns – and it is no laughing matter –
they have done a lot of damage
when I use 3 rows of 6 apples to explain 3 x 6 = 18 –
I propose an illustration – another
propositional form
it’s a way of showing how the game is played
– it’s an aide or a prop to showing how the game is played
application adds nothing to the calculation
the application is a use of the calculation
–
in some descriptive context
‘Suppose that, in order to give an example, I say
“love is a 2-place relation” – am I saying something about love? Of course not. I am giving a rule for the use of the word
“love” and I mean perhaps that we use this
word in such and such a way.’
am I saying something about
love?
quite possibly –
if you think – as most
would – that the word ‘love’ – has application in various contexts
to say ‘love is a 2-place
relation’ –
could well be interpreted
i.e. as saying that love is not a three a place relation – or a four place
relation – or an n-place relation –
giving a rule for the use
of the word – is to define the word –
is to say what it is to
mean –
and therefore what love is
–
and of course any such
proposal –
is open to question – open
to doubt –
is uncertain
‘Yet we do have feeling that when we allude to the
2-place relation ‘love’ we put meaning into the husk of the calculus of
relation. – Imagine a geometrical demonstration carried out using the cylinder
of a lamp instead of a drawing or analytical symbols. How far is this an
application of geometry? Does the use of the glass cylinder in the lamp enter into
the geometrical thought? And does the word “love” in a declaration of love
enter into my discussion of a 2-place relations?’
a geometrical demonstration carried out using the
cylinder of a lamp instead of a drawing or analytical symbols – is an illustration
of the drawing or the analytical symbols
does the glass cylinder enter into the geometrical
thought – or should we say proposal
no – it’s a representation of it
and does the word ‘love’ in a declaration of love
enter into my discussion of 2-place relation?
no
‘We are concerned with different uses or meanings
of the word “application”. “Division is an application of multiplication”. “The
lamp is an application of the glass cylinder”. “The calculation is applied to
these apples”.’
division can be represented as a form of
multiplication
the lamp is a development of the glass cylinder
a calculation is made with these apples
‘At this point we can say: arithmetic is its own
application. The calculus is its own application.
In arithmetic we cannot make preparations for a
grammatical calculation. For if arithmetic is only a game, its application too
is only a game, and either the same game (in which case it takes us no further)
or a different game – and in that case we could play it in pure arithmetic
also.’
yes –
the game’s application is its play
here ‘game’ is a noun – and then a verb –
pure arithmetic – is the game played in the absence
of a descriptive context
it is the same game whatever descriptive context it
is represented in
‘So if the logician says he has made preparations
in arithmetic for the possible existence of 6-place relations, we may ask him:
when what you have prepared finds its application, what will be added to it? A
new calculus? – but that’s something you haven’t provided. Or something that
doesn’t affect the calculus? – then it doesn’t interest us, and the calculus
you have shown us is application enough.’
yes
if someone designs a new calculus – or a new game –
all to the good –
its ‘application’ will be its action – its play
‘What is incorrect is the idea that application of
a calculus in the grammar of real language correlates it to a reality or gives
it a reality that it did not have before.’
the application of a calculus in the grammar of
real language – is the making of a use of the grammar
the grammar of a real language is an account or
theory of a real language
the reality of a real language – is whatever use it
is put to
the application of a calculus in the grammar of
real language
is putting the real language to a particular use
‘Here as so often in this area the mistake lies not
in believing something false, but in looking in the direction of a misleading
analogy.’
the ‘true’ position – or account – is the one you
give your assent to for whatever reason
any use of analogy is open to question – open to
doubt – is uncertain
‘So what happens when the 6-place relation is
found? Is it like the discovery of a metal that has the desired (and previously
described) properties (the right specific weight, strength, etc.)? No; what is
discovered is a word that we in fact use in our language as we used, say the
letter R. “ Yes, but this word has meaning, and ‘R’ has none. So now we see
that something can correspond to ‘R’.” But the meaning of the word does not
consist in something’s corresponding to it, except in a case like that of a
name; but in our case the bearer of the name is merely an extension of the
calculus,
of the language. And it is not like saying “this
story really happened, it was not pure fiction”.’
the ‘discovery’ of a 6-place relation – is the
proposal of a 6-place relation
‘This is all connected with the false concept of
logical analysis that Russell, Ramsey and I used to have, according to which we
are writing for an ultimate logical analysis of facts, like a chemical analysis
of compounds – an analysis which will enable us really to discover a 7-place
relation, like an element that really has the specific weight 7.’
what we deal with is what is before us – that is
proposals – propositions –
any account of – any ‘analysis’ of – a proposal – a
proposition – is itself – a proposal
and any proposal – or any account of a proposal –
is open to question – open to doubt
is uncertain
‘writing for an ultimate logical analysis’ – is
philosophical hubris –
predicated on a corruption of propositional logic
‘Grammar is for us a pure calculus (not the
application of a calculus to reality).’
grammar is a theory of language use – a
language-game –
the game is the reality – when the game is played
‘How can we make preparations for something which
may or may not exist” means how can we hope to make an a priori construction to cope with all possible results while
basing arithmetic upon a logic while we are still waiting for results of an analysis
of our propositions in particular cases?
One wants to say: “we don’t know whether it may not
turn out that there are no functions with 4 argument places, or that there are
only 100 arguments that can significantly be inserted into functions of one variable. Suppose for example (the
supposition does appear possible) that there is only one four place function F
and 4 arguments a, b, b, c, d; does it make sense in that case to say ‘2 + 2 =
4’ since there aren’t any functions to accomplish the division into 2 and 2?”
So now one says to oneself, we will make provision for all possible cases. But
of course that has no meaning. On the one hand the calculus doesn’t make
provision for possible existence; it constructs for itself all the existence
that it needs. On the other hand what looks like hypothetical assumptions about
the logical elements (the logical structure) of the world are merely
specifications of elements in a calculus; and of course you can make these in
such a way that the calculus dose not contain any 2 + 2.
‘an a priori
construction to cope with all possible results’ –
look – any proposal – is open to question – to
doubt –
‘preparations for what may or may not exist’ – are
simply speculative proposals –
it is playing the a priori game – if you like –
and there is no reason why you can’t do this –
any proposal concerning what might happen – is a priori in a sense –
what you have to understand is this –
that a proposal – however you describe it – is open
to question – open to doubt – is uncertain
that goes for so called ‘a priori’ proposals
‘while basing arithmetic upon a logic while we are
still waiting for results of an analysis of our propositions in particular
cases.’ –
arithmetic is a sign game –
any proposal to do with it’s basis – is open to
question – open to doubt – is uncertain
its ‘basis’ – is irrelevant – to the game – to the
playing of the game –
for all intents and purposes – it has no basis – or
its basis is itself –
it is simply a language game – a language practice
– that we engage in – for whatever reason –
if you want to be logical about it – its basis is
no different to the basis of any proposal – any propositional practice –
its basis is uncertainty
yes – ‘the calculus does not make provision for
possible existence’ –
the calculus is a sign game – it does not make
provision – for existence – actual or possible
it is a sign-game construction –
yes – you can – as is done – ascribe existence to the calculus –
hypothesize existence – from the calculus –
but any such speculation has nothing to do with the
calculus as such –
it is just a use of the calculus – in the same way
as any proposal can be used – for purposes for which it was not originally
designed
‘hypothetical assumptions about the logical
elements’ –
so called logical elements are no more than an
interpretation of the calculus –
again the calculus – gets on quite well regardless
of such burdens –
and yes –you can construct any kind of calculus –
any kind of sign game you like –
and underpin it with ‘logical elements’ – and if
you want to then say the ‘the world is thus’ – fair enough –
by all means propose a novel and interesting
metaphysics – in the end we will all be better for it
the one thing to remember though is that any such
proposal – is just that – a proposal
open to question – open to doubt – uncertain
it is really quite irrelevant how a game comes
about –
once it is up and running – that is the point
‘Suppose we make preparations for the existence of
100 objects by introducing a hundred names and a calculus to go with them…
There isn’t any question here of a connection with reality which keeps grammar
on the rails. The “connection of
language with reality”, by means of ostensive definitions and the like, doesn’t
make the grammar inevitable or provide a justification for the grammar. The
grammar remains a free-floating calculus which can only be extended and never
supported. The “connection with reality” merely extends language, it doesn’t
force anything on it. We speak of discovering a 27-place relation but on the
one hand no discovery can force me to use the sign or the calculus for a
27-place relation, and on the other hand I can describe the operation of the
calculus itself simply by using this notation.’
‘Suppose we make preparations for the existence of
100 objects by introducing a hundred names and a calculus to go with them.’ –
we don’t make
preparations for existence – we propose in relation to that which is before
us – that is – the propositions we encounter
and the logic of it is – any proposal – any
proposition – is open to question – open to doubt – is uncertain
our world is a propositional world – a world of
uncertainty –
another way of putting it is to say – what exists –
is uncertain – existence is uncertain
‘There isn’t any question here of a connection with
reality which keeps grammar on the rails’
grammar is a proposal – in relation to language –
to proposals –
it is open to question – open to doubt – it is
uncertain
any grammar – any calculus – is ‘free floating’ –
if by that you mean – open to question – open to doubt – uncertain
a calculus – such as arithmetic – is a
propositional game –
that is a rule governed propositional activity
as played –
it is not in question – not subject to doubt – the game is not uncertain –
games – propositional games – are played as a
relief from question – from doubt – from uncertainty – from logic
of course the propositions that make up a game –
are open to question –
but the game as
played – is not –
our ‘reality’ – is a propositional reality –
a propositional game – is its own reality
the proposition – is reality
‘When it looks in logic as if we are discussing
several different universes (as with Ramsey), in reality we are considering
different games. The definition of a “universe” in a case like Ramsey’s would
simply be a definition like:

a game could be used as a springboard for
metaphysical speculation –
but this is a use of logical games –
it is not logic per se
the real logic of the matter is this –
any proposal – metaphysical or not – is open to
question – open to doubt –
is uncertain
when you play logical games – you are involved in a
rule governed propositional exercise
and if you play – you play in accordance with the
rules – you play without question – without doubt
if you question – if you doubt – you don’t
play the game
metaphysics is not a game
metaphysics is speculation
16. Ramsey’s theory of identity
‘Ramsey’s theory of identity makes the mistake that
would be made by someone who said that you could use a painting as a mirror as
well, even if only for a single posture. If we say this we overlook that what
is essential to a mirror is precisely that you can infer from it the posture of
a body in front of it, whereas in the case of the painting you have to know
that the postures tally before you can construe the picture as a mirror image.’
saying ‘x = y’ – is to say you can substitute x for
y – y for x –
this is not say x is identical to y –
x is not identical to y
x is x – y is y –
there is no identity in x = y
what you have is a proposal for substitution
–
any by that I mean – the proposal that y can
function in place of x – and visa versa –
that two things can substitute for each other – can
behave in the same way –
does not mean they are the same thing
x is x – y is y –
is this to mean x is identical to x – y identical
to y?
I would put that a relation only exists between
different things
so ‘x is x’ – if that means – x is related to x –
then such a statement is meaningless
x is not identical to x –
and the idea that x is a substitute for x – that identity might be explained in terms of
substitution – is ridiculous
in x = y – x is not identical to y – y is not
identical to x –
the concept of identity makes no logical sense –
in the example given above by Wittgenstein – using
a painting as a mirror –
a painting is not a mirror –
and a mirror image is not the thing that is
reflected –
it is an image
of it –
there is no question of identity – even if the painting
– is a good representation of a
particular posture of the subject
the subject and the painting are different things
just as a mirror image and the subject are
different things
the concept of identity is a pseudo concept –
and it is hard to see what logical purpose this
‘identity relation’– could possibly serve in any context –
if I say “yes x is x” – I am proposing x – and at
best by saying “x is x” here – I am
simply giving an emphasis – to x – to its proposal
yes the notion of ‘identity’ is used – and I would
say – works –
as a rhetorical devise
but that is the best you can say for it
Wittgenstein considers Ramsey’s argument for the
identity sign
and goes on to show that Ramsey’s explanation of
the identity sign – fails –
the point being the explanation is of no use
‘If Dirichlet’s conception of function has a strict
sense, it must be expressed in a definition that uses the table to define the
function-signs as equivalent.
Ramsey defines x = y as
(je). je X º je y
But according to the explanation he gives of his
function-sign “je”
(je). je X º je X is the statement: “every sentence
is equivalent to itself”
(je). je X º je y is the statement: “every
sentence is equivalent to every sentence
so all he has achieved by his definition is laid
down by the two definitions
def
x = x . = . Tautology
def
x = y . = . Contradiction’
Wittgenstein continues –
‘It goes without saying that an identity sign
defined like that has no resemblance to the one we use to express a substitution
rule.’
correct
my point here would be that any definition here is
irrelevant – irrelevant to the use of the
‘=’ sign
all you really have from Ramsey is a conception (“je”) –
that is ‘defined’ – that is expressed in other
terms –
i.e. – x = x by definition – a tautology – x = y by
definition – a contradiction –
and we are expected to believe that these terms –
are ‘equivalent to’ – “je” –
when it is ‘equivalent to’ that is up for
definition –
Ramsey’s analysis – even if you accept his identity
sign – (“je”) – and the argument that flows from it – is
ill-conceived
the point here is that ‘=’ – does not require
definition –
it is a sign for the action of substitution –
call that a ‘definition’ – if you like – but
calling it so – is neither here nor there –
the issue is not – how do you define the sign – the
issue is what you do with it –
that is – how it is used –
and that is quite simply a matter of propositional
practise –
which is quite straightforward –
the action of substitution
‘What is in question here is whether functions in
extension are any use; because Ramsey’s explanation of the identity sign is
just such a specification by extension. Now what exactly is the specification
of a function by extension? Obviously it is a group of definitions, e.g.
fa = p Def.
fb = q Def.
fc = r Def.
These definitions permit us to substitute for the
known propositions “p”, “q”, “r” the signs “fa” “fb” “fc”. To say that these
three definitions determine the function f(x) is either to say nothing, or to
say the same as the three definitions say.’
yes – exactly – nothing – nothing on top of nothing
‘Moreover, the purpose of the introduction of
functions in extension was to analyse propositions about infinite extensions,
and it fails of this purpose when a function in extension is introduced by a
list of definitions.’
functions in extension – take us nowhere – but
really the point is – that there is nowhere to go
it doesn’t matter what propositional context you
are operating in – there is no final analysis of any kind – no final definition
–
and the search for such is just woolly headed –
and should just be abandoned as a waste
of time
any program of analysis is open to question – open
to doubt – is uncertain –
the question here – is whether the function in
extension argument has any value in logic – in mathematics
what you have with the function extension is
effectively replication or if you like translation –
no great sin itself – but it does alter focus – and
inevitably introduces considerations that are in fact irrelevant – and
unnecessary –
unnecessary to the game as played – to the playing
of the game –
and if that is so – then such argument in logic and
mathematics – is not logical – but rhetorical –
‘rhetorical’ – that is – if we are to give it any
status at all –
‘useless’ – is more to the point
another way of putting it
is to say –
the function in extension –
is a form of speculation –
and of course there is –
and should be a speculative dimension to logic – to mathematics
but in this context – the
context of the use of the ‘=’ sign in mathematical and logical games – such
speculative argument is out of place –
it’s in the wrong place –
it misses the point
‘There is a temptation to regard the form of an equation as
the form of tautologies and contradictions, because it looks as if one can say
x = x is self evidently true and x = y self evidently false. The comparison
between x = x and a tautology is of course better than that between x = y and a
contradiction, because all correct (and “significant”) equations of mathematics
are actually of the form x = y. We might call x = x
a degenerate equation (Ramsey quite correctly called
tautologies and contradictions degenerate propositions) and indeed a correct
degenerate equation (the limiting case of an equation). For we use expressions
of the form x = x like correct equations, and when we do so we are fully
conscious that we are dealing with degenerate equations. In geometrical proofs
there are propositions in the same case, such as “the angle x is equal to the angle B, the
angle y is equal to itself …”
At this point the
objection might be made that the correct equations of the form x = y must be
tautologies, and incorrect ones contradictions, because it must be possible to
prove a correct equation by transforming each side of it until an identity of
the form
x = x is reached. But although the original equation is
shown to be correct by this process and to that extent the identity x = x is
the goal of the transformation, it is not its goal in the sense that the
purpose of the transformation is to give the equation its correct form – like
bending a crooked object straight; it is not that the equation at long
last achieves its perfect form of identity. So we can’t say:
a correct equation is really an
identity. It just isn’t an identity.’
a tautology is not a proposal – is not a proposition – it is
a corruption – a propositional corruption –
the point of the tautology – is to bring the proposition
process to an end – to bring argument to an end
that is to say to bring an end to question – to doubt – to
uncertainty
the tautology we are told is ‘self-evidently true’ – which
is just a neat turn of phrase for – no more questioning – no more doubt – the
matter is certain
the contradiction – is a straight up denial of propositional
reality – masked – in the form of a proposition –
the contradiction is simply a subversion of logical – that
is – propositional reality
the contradiction brings the propositional process to an end
by denying – or blocking propositional
action
both the tautology and the contradiction – are best seen as
rhetorical devises – rhetorical devises – impersonating logical forms
to say that mathematical games are played with rhetorical
devises – or that logical games are played with rhetorical devises – might
strike some as quite an outrageous statement –
the fact is that if a game is to be – if it is to be played
– logic – question – doubt uncertainty – must be circumvented – and this is
where rhetorical devises come into play
it is in logic and mathematics that some of the most
effective rhetorical devises have been devised – i.e. – the tautology – the
contradiction – the proof
as to the form of the equation –
what we can say of the equation is that it is a
propositional game – a game of substitution
identity doesn’t figure in it
17. The concept of the application of arithmetic (mathematics)
‘If I say “it must be
essential to mathematics that it can be applied” we mean that its applicability isn’t the kind of thing I mean
of a piece of wood when I say “I will be able to find many applications for
it”.’
mathematics is not an
application –
rather it is better
understood as the theory of application
‘Geometry isn’t the science
(the natural science) of geometric planes, lines and points, as opposed to some
other science of gross physical lines, stripes and surfaces and their properties. The relation between
geometry and propositions of practical life, about stripes, color boundaries,
edges and corners, etc. isn’t the things geometry speaks of, though ideal edges and corners resemble those
spoken of in practical propositions and their grammar. Applied geometry is the
grammar of statements about spatial objects. The relation between what is
called a geometrical line and a boundary between two colours isn’t like the
relation between something fine and something course, but like the relation
between possibility and actuality. (Think of the notion of
possibility as a shadow of
actuality.)’
yes – geometry is a rule
governed propositional game –
applied geometry – is the
game played in context – the context of physical lines – stripes – surfaces and
their properties –
‘The relation between what
is called a geometrical line and a boundary between two colours isn’t like the
relation between something fine and something course …’
no it’s the relation
between two proposals –
a geometrical proposition
and a physical proposition –
and this propositional
relation – is open to account – to description
‘but like the relation
between possibility and actuality. (Think of the notion of
possibility as a shadow of
actuality.)’
here we have one such
account – one such description
‘You can describe a circular surface divided
diametrically into 8 congruent parts, but it is senseless to give such a
description of an elliptical surface. And that contains all that geometry says in
this connection about circular and elliptical surfaces.’
‘describing a circular surface’ –
is to propose that a particular geometrical game be
played – in a particular context
‘a circular context’ –
is no more than the proposal that the playing of that
game will be useful
the same game in a different context – may not work
– may not be useful –
game utility – is open to question – open to doubt
– is uncertain
‘(A proposition based on a wrong calculation (such
as ‘he cut a 3 metre board into 4 one metre parts” is nonsensical, and that
throws light on what is meant by “making sense” and “meaning something by a
proposition”.)’
is ‘he cut a 3 meter board into 4 one metre parts’
– nonsensical?
what we are likely to say of the proposition – is
that it represents – a failure to understand the rules of arithmetic – the
rules of the arithmetic game –
as an illustration
of that – it is not – nonsensical –
relative to the rules of arithmetic – it ‘makes
sense’ – and ‘means something’ – as an
example of not properly applying
those rules – of what not to do – if
you want to play the game
in this respect such a proposal – such a
proposition – is quite pertinent
the point is that this proposition – as with any
proposition – is open –
open to question – open to doubt –
if it was not open – open to question – it would
not be a proposal – it would not be a proposition –
it wouldn’t be here
– and if it wasn’t here –
obviously we wouldn’t be discussing it
‘What about the proposition “the sum of all angles
of a triangle is 180°”? At all events you can’t tell by looking at it that it
is a proposition of syntax.
The proposition “corresponding angles are equal”
means that if they don’t appear equal when they are measured I will treat the
measurement as incorrect; and “the sum of the angles of a triangle is 180°”
means that if it doesn’t appear to be 180 degrees when they are measured I will
assume that there has been a mistake in the measurement. So the proposition is
a postulate about the method of describing facts, and therefore a proposition
of syntax.’
the proposition “the sum of all angles of a
triangle is 180° is a game proposition
appearance here is irrelevant
the game as such – is not open to questions of
truth or falsity – it is not correct or incorrect
it is not a postulate about the method of
describing facts – it is a propositional game –
and yes – it can be described as a proposition of syntax
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