5.5521 And if this were not the case, how could we apply logic? We could say: if there were a logic, even if there were no world, how then could there be a logic, since there is a world ?
5.553 Russell said that there were simple relations between different numbers of things (individuals). But between what numbers? And how should this be decided — by experience ?
(There is no pre-eminent number.)
5.554 The enumeration of any special forms would be entirely arbitrary.
5.5541 How could we decide a priori whether, for example, I can get into a situation in which I need to symbolize with a sign of a 27-termed relation ?
5.5542 May we then ask this at all? Can we set out a sign form and not know whether anything can correspond to it?
Has the question sense: what must there be in order that anything can be the case?
5.555 It is clear that we have a concept of the elementary proposition apart from its special logical form.
Where, however, we can build symbols according to a system, there this system is the logically important thing and not the single symbols.
And how would it be possible that I should have to deal with forms in logic which I can invent: but I must have to deal with that which makes it possible for me to invent them.
5.556 There cannot be a hierarchy of the forms of the elementary propositions. Only that which we ourselves construct can we foresee.
5.5561 Empirical reality is limited by the totality of objects. The boundary appears again in thetotality of elementary propositions.