ss the whole of logical space must already be given by it.
(Otherwise negation, logical sum, logical product, etc., would introduce
more and more new elements in co-ordination.) (The logical scaffolding
surrounding a picture determines logical space. The force of a
proposition reaches through the whole of logical space.)

3.5 A propositional sign, applied and thought out, is a thought.

4. A thought is a proposition with a sense.

4.001 The totality of propositions is language.

4.022 Man possesses the ability to construct languages capable of
expressing every sense, without having any idea how each word has
meaning or what its meaning is--just as people speak without knowing how
the individual sounds are produced. Everyday language is a part of the
human organism and is no less complicated than it. It is not humanly
possible to gather immediately from it what the logic of language is.
Language disguises thought. So much so, that from the outward form of
the clothing it is impossible to infer the form of the thought beneath
it, because the outward form of the clothing is not designed to reveal
the form of the body, but for entirely different purposes. The tacit
conventions on which the understanding of everyday language depends are
enormously complicated.

4.003 Most of the propositions and questions to be found in
philosophical works are not false but nonsensical. Consequently we
cannot give any answer to questions of this kind, but can only point
out that they are nonsensical. Most of the propositions and questions
of philosophers arise from our failure to understand the logic of our
language. (They belong to the same class as the question whether the
good is more or less identical than the beautiful.) And it is not
surprising that the deepest problems are in fact not problems at all.

4.0031 All philosophy is a 'critique of language' (though not in
Mauthner's sense). It was Russell who performed the service of showing
that the apparent logical form of a proposition need not be its real
one.

4.01 A proposition is a picture of reality. A proposition is a model of
reality as we imagine it.

4.011 At first sight a proposition--one set out on the printed page, for
example--does not seem to be a picture of the reality with which it
is concerned. But neither do written notes seem at first sight to be a
picture of a piece of music, nor our phonetic notation (the alphabet)
to be a picture of our