Combining Texts

All the ideas for 'Reason, Emotions and Good Life', 'The Logic of Boundaryless Concepts' and 'Notes on Logic'

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4 ideas

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

9390	Logic guides thinking, but it isn't a substitute for it [Rumfitt]
	Full Idea: Logic is part of a normative theory of thinking, not a substitute for thinking.
	From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.13)
	A reaction: There is some sort of logicians' dream, going back to Leibniz, of a reasoning engine, which accepts propositions and outputs inferences. I agree with this idea. People who excel at logic are often, it seems to me, modest at philosophy.

7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts

22312	Facts can be both positive and negative [Wittgenstein, by Potter]
	Full Idea: In 1913 Wittgenstein was explicit that there are both positive and negative facts.
	From: report of Ludwig Wittgenstein (Notes on Logic [1913], B7) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 47 'Mole'
	A reaction: This is a prelude to the Tractatus, in which negative facts are denied in T1.11 (and in a 1919 letter), but then affirmed in T2.06.

9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects

9389	Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt]
	Full Idea: Vagueness in respect of membership is consistency with determinacy of the set's identity, so long as a set's identity is taken to consist, not in its having such-and-such members, but in its being the extension of a concept.
	From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.5)
	A reaction: I find this view of sets much more appealing than the one that identifies a set with its members. The empty set is less of a problem, as well as non-existents. Logicians prefer the extensional view because it is tidy.

20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason

4316	Either all action is rational, or reason dominates, or reason is only concerned with means [Cottingham]
	Full Idea: We can distinguish rational exclusivism (all activity is guided by reason - Plato and Spinoza), rational hegemonism (all action is dominated by reason), and rational instrumentalism (reason assesses means rather than ends - Hume).
	From: John Cottingham (Reason, Emotions and Good Life [2000])
	A reaction: The idea that reason is the only cause of actions seems deeply implausible, but I strongly resist Hume's instrumental approach. Action without desire is not a contradiction.