Tuesday, November 20, 2007

6.122 From which it follows that we can go on without logical propositions, since we can perceive in an appropriate notation the formal properties of propositions with a simple look at these propositions.

What would such a notation be?

Black (p. 324) suggests ‘corresponding’ for entsprechend where P&McG have ‘suitable’ and I have ‘appropriate.’ He adds that “In a sense, every notation is suitable.” On p. 325 he says that “in a sense, every notation is ‘adequate’ to express whatever meaning it expresses.”

White (p. 105): “Wittgenstein goes badly astray in his development of this train of thought [i.e. that found in the 6.1s], and subsequent developments in logic [Alonzo Church, 1936] have shown that what he says at 6.122 is demonstrably false.” On p. 107 he writes: “What Wittgenstein overlooks is that once he allows the possibility of there being infinitely many elementary propositions, he has to allow the possibility of quantification over infinite domains. If we then have propositions involving multiple quantifiers ranging over infinite domains, then even the most perspicuous notation may not be able to display the information that a given proposition is a tautology in a form that is surveyable by us. So that even if we continue to say that a tautology shows that it is such, it may not do so in a form that is recognizable by us: we may simply lack any method for extracting the fact that it is a tautology. This means that in this use of the concept of ‘showing’ at least, ‘showing’ cannot be treated as a straightforward epistemological concept.”

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