15 ideas
7910 | Pursue truth with the urgency of someone whose clothes are on fire [Ashvaghosha] |
Full Idea: As though your turban or your clothes were on fire, so with a sense of urgency should you apply your intellect to the comprehension of the truths. | |
From: Ashvaghosha (Saundaranandakavya [c.50], XVI) | |
A reaction: The best philosophers need no such urging. I retain a romantic view that we should be 'natural' in these things. See Plato's views in Idea 2153 and 1638. However, maybe I should be confronted with this quotation every morning when I awake. |
13011 | New axioms are being sought, to determine the size of the continuum [Maddy] |
Full Idea: In current set theory, the search is on for new axioms to determine the size of the continuum. | |
From: Penelope Maddy (Believing the Axioms I [1988], §0) | |
A reaction: This sounds the wrong way round. Presumably we seek axioms that fix everything else about set theory, and then check to see what continuum results. Otherwise we could just pick our continuum, by picking our axioms. |
13013 | The Axiom of Extensionality seems to be analytic [Maddy] |
Full Idea: Most writers agree that if any sense can be made of the distinction between analytic and synthetic, then the Axiom of Extensionality should be counted as analytic. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.1) | |
A reaction: [Boolos is the source of the idea] In other words Extensionality is not worth discussing, because it simply tells you what the world 'set' means, and there is no room for discussion about that. The set/class called 'humans' varies in size. |
13014 | Extensional sets are clearer, simpler, unique and expressive [Maddy] |
Full Idea: The extensional view of sets is preferable because it is simpler, clearer, and more convenient, because it individuates uniquely, and because it can simulate intensional notions when the need arises. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.1) | |
A reaction: [She cites Fraenkel, Bar-Hillet and Levy for this] The difficulty seems to be whether the extensional notion captures our ordinary intuitive notion of what constitutes a group of things, since that needs flexible size and some sort of unity. |
13021 | The Axiom of Infinity states Cantor's breakthrough that launched modern mathematics [Maddy] |
Full Idea: The Axiom of Infinity is a simple statement of Cantor's great breakthrough. His bold hypothesis that a collection of elements that had lurked in the background of mathematics could be infinite launched modern mathematics. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.5) | |
A reaction: It also embodies one of those many points where mathematics seems to depart from common sense - but then most subjects depart from common sense when they get more sophisticated. Look what happened to art. |
13022 | Infinite sets are essential for giving an account of the real numbers [Maddy] |
Full Idea: If one is interested in analysis then infinite sets are indispensable since even the notion of a real number cannot be developed by means of finite sets alone. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.5) | |
A reaction: [Maddy is citing Fraenkel, Bar-Hillel and Levy] So Cantor's great breakthrough (Idea 13021) actually follows from the earlier acceptance of the real numbers, so that's where the departure from common sense started. |
13023 | The Power Set Axiom is needed for, and supported by, accounts of the continuum [Maddy] |
Full Idea: The Power Set Axiom is indispensable for a set-theoretic account of the continuum, ...and in so far as those attempts are successful, then the power-set principle gains some confirmatory support. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.6) | |
A reaction: The continuum is, of course, notoriously problematic. Have we created an extra problem in our attempts at solving the first one? |
13024 | Efforts to prove the Axiom of Choice have failed [Maddy] |
Full Idea: Jordain made consistent and ill-starred efforts to prove the Axiom of Choice. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.7) | |
A reaction: This would appear to be the fate of most axioms. You would presumably have to use a different system from the one you are engaged with to achieve your proof. |
13025 | Modern views say the Choice set exists, even if it can't be constructed [Maddy] |
Full Idea: Resistance to the Axiom of Choice centred on opposition between existence and construction. Modern set theory thrives on a realistic approach which says the choice set exists, regardless of whether it can be defined, constructed, or given by a rule. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.7) | |
A reaction: This seems to be a key case for the ontology that lies at the heart of theory. Choice seems to be an invaluable tool for proofs, so it won't go away, so admit it to the ontology. Hm. So the tools of thought have existence? |
13026 | A large array of theorems depend on the Axiom of Choice [Maddy] |
Full Idea: Many theorems depend on the Axiom of Choice, including that a countable union of sets is countable, and results in analysis, topology, abstract algebra and mathematical logic. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.7) | |
A reaction: The modern attitude seems to be to admit anything if it leads to interesting results. It makes you wonder about the modern approach of using mathematics and logic as the cutting edges of ontological thinking. |
13019 | The Iterative Conception says everything appears at a stage, derived from the preceding appearances [Maddy] |
Full Idea: The Iterative Conception (Zermelo 1930) says everything appears at some stage. Given two objects a and b, let A and B be the stages at which they first appear. Suppose B is after A. Then the pair set of a and b appears at the immediate stage after B. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.3) | |
A reaction: Presumably this all happens in 'logical time' (a nice phrase I have just invented!). I suppose we might say that the existence of the paired set is 'forced' by the preceding sets. No transcendental inferences in this story? |
13018 | Limitation of Size is a vague intuition that over-large sets may generate paradoxes [Maddy] |
Full Idea: The 'limitation of size' is a vague intuition, based on the idea that being too large may generate the paradoxes. | |
From: Penelope Maddy (Believing the Axioms I [1988], §1.3) | |
A reaction: This is an intriguing idea to be found right at the centre of what is supposed to be an incredibly rigorous system. |
15314 | Faraday's single field of variable forces introduces a criterion of Unity into what is ultimate [Faraday, by Harré/Madden] |
Full Idea: In Faraday lines of force picture the directional structure of powers,...so the fundamental entity is a single, unified field. ...A new criterion of the ultimate has stepped in: Unity. The universal field is still the final explanation, but not invariant. | |
From: report of Michael Faraday (Experimental Researches in Electricity [1859]) by Harré,R./Madden,E.H. - Causal Powers 9.II.B | |
A reaction: Almost Parmenides, except that the field is not invariant. But that was always the ancient objection to the One - that it offered no explanation of change. |
7909 | The Eightfold Path concerns morality, wisdom, and tranquillity [Ashvaghosha] |
Full Idea: The Eightfold Path has three steps concerning morality - right speech, right bodily action, and right livelihood; three of wisdom - right views, right intentions, and right effort; and two of tranquillity - right mindfulness and right concentration. | |
From: Ashvaghosha (Saundaranandakavya [c.50], XVI) | |
A reaction: Most of this translates quite comfortably into the aspirations of western philosophy. For example, 'right effort' sounds like Kant's claim that only a good will is truly good (Idea 3710). The Buddhist division is interesting for action theory. |
7908 | At the end of a saint, he is not located in space, but just ceases to be disturbed [Ashvaghosha] |
Full Idea: When an accomplished saint comes to the end, he does not go anywhere down in the earth or up in the sky, nor into any of the directions of space, but because his defilements have become extinct he simply ceases to be disturbed. | |
From: Ashvaghosha (Saundaranandakavya [c.50], XVI) | |
A reaction: To 'cease to be disturbed' is the most attractive account of heaven I have encountered. It all sounds a bit dull though. I wonder, as usual, how they know all this stuff. |