Combining Texts

All the ideas for 'Mahaprajnaparamitashastra', 'Continuity and Irrational Numbers' and 'Aristotle on Substance'

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8 ideas

6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
17611 We want the essence of continuity, by showing its origin in arithmetic [Dedekind]
     Full Idea: It then only remained to discover its true origin in the elements of arithmetic and thus at the same time to secure a real definition of the essence of continuity.
     From: Richard Dedekind (Continuity and Irrational Numbers [1872], Intro)
     A reaction: [He seeks the origin of the theorem that differential calculus deals with continuous magnitude, and he wants an arithmetical rather than geometrical demonstration; the result is his famous 'cut'].
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
10572 A cut between rational numbers creates and defines an irrational number [Dedekind]
     Full Idea: Whenever we have to do a cut produced by no rational number, we create a new, an irrational number, which we regard as completely defined by this cut.
     From: Richard Dedekind (Continuity and Irrational Numbers [1872], §4)
     A reaction: Fine quotes this to show that the Dedekind Cut creates the irrational numbers, rather than hitting them. A consequence is that the irrational numbers depend on the rational numbers, and so can never be identical with any of them. See Idea 10573.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
17612 Arithmetic is just the consequence of counting, which is the successor operation [Dedekind]
     Full Idea: I regard the whole of arithmetic as a necessary, or at least natural, consequence of the simplest arithmetic act, that of counting, and counting itself is nothing else than the successive creation of the infinite series of positive integers.
     From: Richard Dedekind (Continuity and Irrational Numbers [1872], §1)
     A reaction: Thus counting roots arithmetic in the world, the successor operation is the essence of counting, and the Dedekind-Peano axioms are built around successors, and give the essence of arithmetic. Unfashionable now, but I love it. Intransitive counting?
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / l. Limits
18087 If x changes by less and less, it must approach a limit [Dedekind]
     Full Idea: If in the variation of a magnitude x we can for every positive magnitude δ assign a corresponding position from and after which x changes by less than δ then x approaches a limiting value.
     From: Richard Dedekind (Continuity and Irrational Numbers [1872], p.27), quoted by Philip Kitcher - The Nature of Mathematical Knowledge 10.7
     A reaction: [Kitcher says he 'showed' this, rather than just stating it]
9. Objects / C. Structure of Objects / 3. Matter of an Object
16083 Aristotelian matter seriously threatens the intrinsic unity and substantiality of its object [Gill,ML]
     Full Idea: On the interpretation of Aristotelian matter that I shall propose, matter seriously threatens the intrinsic unity, and hence the substantiality, of the object to which it contributes.
     From: Mary Louise Gill (Aristotle on Substance [1989], Intro)
     A reaction: Presumably the thought is that if an object is form+matter (hylomorphism), then forms are essentially unified, but matter is essentially unified and sloppy.
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
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').
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / b. Prime matter
17006 Prime matter has no place in Aristotle's theories, and passages claiming it are misread [Gill,ML]
     Full Idea: I argue that prime matter has no place in Aristotle's elemental theory. ..References to prime matter are found in Aristotle's work because his theory was thought to need the doctrine. If I am right, these passages will all admit of another interpretation.
     From: Mary Louise Gill (Aristotle on Substance [1989], App)
     A reaction: If correct, this strikes me as important for the history of ideas, because scholastics got themselves in a right tangle over prime matter. See Pasnau on it. It pushed the 17th century into corpuscularianism.
16093 Prime matter is actually nothing and potentially everything (or potentially an element) [Gill,ML]
     Full Idea: Prime matter is supposed to be actually nothing and potentially everything or, at any rate, potentially the simplest bodies - earth, water, air and fire.
     From: Mary Louise Gill (Aristotle on Substance [1989], Ch.1)
     A reaction: The view that the four elements turn out to be prime matter is distinctive of Gill's approach. Prime matter sounds like quark soup in the early universe.