Combining Texts

All the ideas for 'The Sign of Four', 'Letters to a German Princess' and 'Presupposition'

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4 ideas

4. Formal Logic / A. Syllogistic Logic / 3. Term Logic

19053	Logic would be more natural if negation only referred to predicates [Dummett]
	Full Idea: A better proposal for a formal logic closer to natural language would be one that had a negation-operator only for (simple) predicates.
	From: Michael Dummett (Presupposition [1960], p.27)
	A reaction: Dummett observes that classical formal logic was never intended to be close to natural language. Term logic does have that aim, but the meta-question is whether that end is desirable, and why.

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / c. not

19052	Natural language 'not' doesn't apply to sentences [Dummett]
	Full Idea: Natural language does not possess a sentential negation-operator.
	From: Michael Dummett (Presupposition [1960], p.27)
	A reaction: This is a criticism of Strawson, who criticises logic for not following natural language, but does it himself with negation. In the question of how language and logic connect, this idea seems important. Term Logic aims to get closer to natural language.

14. Science / C. Induction / 1. Induction

22200	If you eliminate the impossible, the truth will remain, even if it is weird [Conan Doyle]
	Full Idea: When you have eliminated the impossible, whatever remains, however improbable, must be the truth.
	From: Arthur Conan Doyle (The Sign of Four [1890], Ch. 6)
	A reaction: A beautiful statement, by Sherlock Holmes, of Eliminative Induction. It is obviously not true, of course. Many options may still face you after you have eliminated what is actually impossible.

26. Natural Theory / D. Laws of Nature / 1. Laws of Nature

5467	Euler said nature is instrinsically passive, and minds cause change [Euler, by Ellis]
	Full Idea: Euler thought the powers necessary for the maintenance of the changing universe would turn out to be just the passive ones of inertia and impenetrability. There are no active powers, he urged, other than those of God and living beings.
	From: report of Leonhard Euler (Letters to a German Princess [1765]) by Brian Ellis - The Philosophy of Nature: new essentialism Ch.4
	A reaction: Very significant, I think, for revealing the religious framework behind early theories of natural laws. If there is nothing external to impose powers and movements on nature, the source must be sought within - hence essentialism.