4 ideas
6408 | Russell needed three extra axioms to reduce maths to logic: infinity, choice and reducibility [Grayling] |
Full Idea: In order to deduce the theorems of mathematics from purely logical axioms, Russell had to add three new axioms to those of standards logic, which were: the axiom of infinity, the axiom of choice, and the axiom of reducibility. | |
From: A.C. Grayling (Russell [1996], Ch.2) | |
A reaction: The third one was adopted to avoid his 'barber' paradox, but many thinkers do not accept it. The interesting question is why anyone would 'accept' or 'reject' an axiom. |
6414 | Two propositions might seem self-evident, but contradict one another [Grayling] |
Full Idea: Two propositions might contradict each other despite appearing self-evident when considered separately. | |
From: A.C. Grayling (Russell [1996], Ch.2) | |
A reaction: Russell's proposal (Idea 5416) is important here, that self-evidence comes in degrees. If self-evidence was all-or-nothing, Grayling's point would be a major problem, but it isn't. Bonjour explores the idea more fully (e.g. Idea 3704) |
7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom. | |
From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88) | |
A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate'). |
19436 | Bare or primary matter is passive; it is clothed or secondary matter which contains action [Leibniz] |
Full Idea: The active principle is not attributed by me to bare or primary matter, which is merely passive ...but to clothed or secondary matter which in addition contains a primitive entelechy, or active principle. | |
From: Gottfried Leibniz (Letters to Wagner [1710], 1710 §2) | |
A reaction: Secondary matter contains monads. The puzzling question is what primary matter consists of. It is not atoms, because it is infinitely divisible, and it seems to be composed of corpuscles. But what is it made of? Just gunge? He says it is 'flux'. |