Ludwig Wittgenstein (1922) : Tractatus logico-philosphicus.
2.063 The total reality is the world.
2.1 We make ourselves pictures of facts.
2.11 The picture presents the facts in logical space, the existence and non-existence of
atomic facts.
2.12 The picture is the model of reality.
2.13 To the objects correspond in the picture the elements of the picture.
2.131 The elements of the picture stand, in the picture, for the objects.
2.141 The picture is a fact.
2.151 The form of representation is the possibility that the things are combined with one
another as are the elements of the picture.
2.1511 Thus the picture is linked with reality; it reaches up to it.
2.1512 It is like a scale applied to reality.
2.161 In the picture and the pictured there must be something identical in order that the
one can be a picture of the other at all.
2.171 The picture can represent every reality whose form it has.
2.18 What every picture, of whatever form, must have in common with reality in order to
be able to represent it at all – rightly or falsely – is the logical form, that is, the form of
reality.
2.19 The logical picture can depict the world.
2.21 The picture agrees with reality or not; it is right or wrong, true or false.
2.223 In order to discover whether the picture is true or false, we must compare it with
reality.
3.01 The totality of true thoughts is a picture of the world.
3.032 To present in language anything which ‘contradicts logic’ is as impossible as in
geometry to present by its co-ordinates a figure which contradicts the laws of space; or to
give the co-ordinates of a point which does not exist.
3.12 The sign through which we express the thought I call the propositional sign. And the
proposition is the propositional sign in its projective relation to the world.
3.323 In the language of everyday life it very often happens that the same word signifies in
two different ways – and therefore belongs to two different symbols – or that of two words,
which signify in different ways, are apparently applied in the same way in the proposition.
3.324 Thus there easily arise the most fundamental confusion (of which the whole of
philosophy is full).
3.325 I order to avoid these errors, we must employ a symbolism which excludes them, by
not applying the same sign in different symbols and by not applying signs in the same way
which signify in different ways. A symbolism, that is to say, which obeys the rules of logical
grammar – of logical syntax.
4 The thought is the significant proposition
4.001 The totality of propositions is the language
4.002 Man possesses the capacity of constructing languages, in which every sense can be
expressed without having an idea how and what each word means – just as one speaks
without knowing how the single sounds are produced. Colloquial language is a part of the
human organism and it is not less complicated than it. Language disguises the thought; so
that from the external form of the clothes one cannot infer the form of the thought they
clothe; because the external form of the clothes is constructed with quite another object
than to let the form of the body be recognized. The silent adjustments to understand
colloquial language are enormously complicated.
4.0031 All philosophy is ‘Critique of language’ (…)
4.01 The proposition is a picture of reality. The proposition is a model of reality as we
think it is.
4.05 Reality is compared with the proposition.
4.06 Propositions can be true or false only by being pictures of the reality.
7 Whereof one cannot speak, thereof one must be silent.
