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Ideas for 'Mahaprajnaparamitashastra', 'Foundations of Two-Dimensional Semantics' and 'Writing the Book of the World'

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6 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
There is a real issue over what is the 'correct' logic [Sider]
     Full Idea: Certain debates over the 'correct' logic are genuine, and not linguistic or conceptual.
     From: Theodore Sider (Writing the Book of the World [2011], 01.3)
     A reaction: It is rather hard to give arguments in favour of this view, but I am pleased to have the authority of Sider with me.
'It is raining' and 'it is not raining' can't be legislated, so we can't legislate 'p or ¬p' [Sider]
     Full Idea: I cannot legislate-true 'It is raining' and I cannot legislate true 'It is not raining', so if I cannot legislate either true then I cannot legislate-true the disjunction 'it is raining or it is not raining'.
     From: Theodore Sider (Writing the Book of the World [2011], 06.5)
     A reaction: This strikes me as a very simple and very persuasive argument against the idea that logic is a mere convention. I take disjunction to be an abstract summary of how the world works. Sider seems sympathetic.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic is good for mathematics and science, but less good for natural language [Sider]
     Full Idea: Despite its brilliant success in mathematics and fundamental science, classical logic applies uneasily to natural language.
     From: Theodore Sider (Writing the Book of the World [2011], 10.6)
     A reaction: He gives examples of the conditional, and debates over the meaning of 'and', 'or' and 'not', and also names and quantifiers. Many modern philosophical problems result from this conflict.
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Modal accounts of logical consequence are simple necessity, or essential use of logical words [Sider]
     Full Idea: The simplest modal account is that logical consequence is just necessary consequence; another modal account says that logical consequences are modal consequences that involve only logical words essentially.
     From: Theodore Sider (Writing the Book of the World [2011], 12.3)
     A reaction: [He cites Quine's 'Carnap and Logical Truth' for the second idea] Sider is asserting that Humeans like him dislike modality, and hence need a nonmodal account of logical consequence.
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider]
     Full Idea: Some say that logical constants are those expressions that are defined by their proof-theoretic roles, others that they are the expressions whose semantic values are permutation-invariant, and still others that they are the topic-neutral expressions.
     From: Theodore Sider (Writing the Book of the World [2011], 10.3)
     A reaction: [He cites MacFarlane 2005 as giving a survey of this]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
'Tonk' is supposed to follow the elimination and introduction rules, but it can't be so interpreted [Sider]
     Full Idea: 'Tonk' is stipulated by Prior to stand for a meaning that obeys the elimination and introduction rules; but there simply is no such meaning; 'tonk' cannot be interpreted so as to obey the rules.
     From: Theodore Sider (Writing the Book of the World [2011], 06.5)
     A reaction: 'Tonk' thus seems to present a problem for so-called 'natural' deduction, if the natural deduction consists of nothing more than obey elimination and introduction rules.