7 ideas
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. |
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. |
13554 | True greatness is never allowing events to disturb you [Seneca] |
Full Idea: There is no more reliable proof of greatness than to be in a state where nothing can happen to make you disturbed. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §06) | |
A reaction: He specifically opposes Aristotle's view that there are times when anger is appropriate, and failure to be very angry indeed is a failure of character. |
13556 | Every night I critically review how I have behaved during the day [Seneca] |
Full Idea: When the lamp has been removed from my sight, and my wife, no stranger now to my habit, has fallen silent, I examine the whole of my day and retrace my actions and words; I hide nothing from myself. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §36) |
13552 | Anger is an extreme vice, threatening sanity, and gripping whole states [Seneca] |
Full Idea: Other vices drive the mind on, anger hurls it headlong; ..other vices revolt from good sense, this one from sanity; ...other vices seize individuals, this is the one passion that sometimes takes hold of an entire state. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §01) | |
A reaction: He particularly dislikes anger because it is the vice that leads to violence. |
13553 | Anger is a vice which afflicts good men as well as bad [Seneca] |
Full Idea: Other vile passions affect only the worst sort of men, but anger creeps up even on enlightened me who are otherwise sane. | |
From: Seneca the Younger (On Anger (Book 3) [c.60], §04) | |
A reaction: A very interesting observation for anyone who is trying to analyse the key issues in virtue theory. |
17009 | I won't object if someone shows that gravity consistently arises from the action of matter [Newton] |
Full Idea: If someone explains gravity along with all its laws by the action of some subtle matter, and shows that the motion of the planets and comets will not be disturbed by this matter, I shall be far from objecting. | |
From: Isaac Newton (Letters to Leibniz 1 [1693], 1693.10.16) | |
A reaction: Important if you think that Newton is the hero of the descriptive regularity theory of laws. Newton probably thought laws came from God, but he wouldn't object to Leibniz's view, that God planted the laws within the matter. |