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All the ideas for '', 'Parthood and Identity across Time' and 'talk'

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7 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic

11211	If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
	Full Idea: If a designated conclusion follows from the premisses, but the argument involves two howlers which cancel each other out, then the moral is that the path an argument takes from premisses to conclusion does matter to its logical evaluation.
	From: Ian Rumfitt ("Yes" and "No" [2000], II)
	A reaction: The drift of this is that our view of logic should be a little closer to the reasoning of ordinary language, and we should rely a little less on purely formal accounts.

5. Theory of Logic / A. Overview of Logic / 3. Value of Logic

10152	Set theory and logic are fairy tales, but still worth studying [Tarski]
	Full Idea: People have asked me, 'How can you, a nominalist, do work in set theory and in logic, which are theories about things you do not believe in?' ...I believe that there is a value even in fairy tales and the study of fairy tales.
	From: Alfred Tarski (talk [1965]), quoted by Feferman / Feferman - Alfred Tarski: life and logic
	A reaction: This is obviously an oversimplification. I don't think for a moment that Tarski literally believed that the study of fairy tales had as much value as the study of logic. Why do we have this particular logic, and not some other?

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

11210	Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
	Full Idea: If 'and' and 'but' really are alike in sense, in what might that likeness consist? Some philosophers of classical logic will reply that they share a sense by virtue of sharing a truth table.
	From: Ian Rumfitt ("Yes" and "No" [2000])
	A reaction: This is the standard view which Rumfitt sets out to challenge.

11212	The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
	Full Idea: A connective will possess the sense that it has by virtue of its competent users' finding certain rules of inference involving it to be primitively obvious.
	From: Ian Rumfitt ("Yes" and "No" [2000], III)
	A reaction: Rumfitt cites Peacocke as endorsing this view, which characterises the logical connectives by their rules of usage rather than by their pure semantic value.

8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism

10151	I am a deeply convinced nominalist [Tarski]
	Full Idea: I am a nominalist. This is a very deep conviction of mine. ...I am a tortured nominalist.
	From: Alfred Tarski (talk [1965]), quoted by Feferman / Feferman - Alfred Tarski: life and logic Int I
	A reaction: I too am of the nominalist persuasion, but I don't feel justified in such a strong commitment.

9. Objects / E. Objects over Time / 5. Temporal Parts

13267	Temporal parts is a crazy doctrine, because it entails constantly creating stuff ex nihilo [Thomson, by Koslicki]
	Full Idea: Thomson famously objects that the doctrine of temporal parts is 'a crazy metaphysic - obviously false', since it entails that material objects are constantly being generated ex nihilo (or, at least, the stuff of which they are composed is).
	From: report of Judith (Jarvis) Thomson (Parthood and Identity across Time [1983], p.210) by Kathrin Koslicki - The Structure of Objects 2.2
	A reaction: The related objections are to ask what the temporal 'width' of a part is, and whether the joins are visible.

19. Language / F. Communication / 3. Denial

11214	We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
	Full Idea: The standard view is that affirming not-A is more complex than affirming the atomic sentence A itself, with the latter determining its sense. But we could learn 'not' directly, by learning at once how to either affirm A or reject A.
	From: Ian Rumfitt ("Yes" and "No" [2000], IV)
	A reaction: [compressed] This seems fairly anti-Fregean in spirit, because it looks at the psychology of how we learn 'not' as a way of clarifying what we mean by it, rather than just looking at its logical behaviour (and thus giving it a secondary role).