Combining Texts

All the ideas for 'Bayesianism', 'Continuity and Irrational Numbers' and 'Manuscript remains'

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9 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophers can't be religious, and don't need to be; philosophy is perilous but free [Schopenhauer]
     Full Idea: No one who is religious attains to philosophy; he does not need it. No one who really philosophizes is religious; he walks without leading-strings, perilously but free.
     From: Arthur Schopenhauer (Manuscript remains [1855], II p.241-3), quoted by Peter B. Lewis - Schopenhauer 3
     A reaction: This is a direct reply to the opposite view expressed by Schleiermacher (and quoted by Lewis). I would say that to be a philosopher one must give priority to the philosophy, ahead of any religious beliefs. Thinking must be free.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
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
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
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
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]
14. Science / C. Induction / 6. Bayes's Theorem
Probability of H, given evidence E, is prob(H) x prob(E given H) / prob(E) [Horwich]
     Full Idea: Bayesianism says ideally rational people should have degrees of belief (not all-or-nothing beliefs), corresponding with probability theory. Probability of H, given evidence E, is prob(H) X prob(E given H) / prob(E).
     From: Paul Horwich (Bayesianism [1992], p.41)
Bayes' theorem explains why very surprising predictions have a higher value as evidence [Horwich]
     Full Idea: Bayesianism can explain the fact that in science surprising predictions have greater evidential value, as the equation produces a higher degree of confirmation.
     From: Paul Horwich (Bayesianism [1992], p.42)
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
As the subject of willing I am wretched, but absorption in knowledge is bliss [Schopenhauer]
     Full Idea: As the subject of willing I am an exceedingly wretched being, and all our suffering consistd in willing, ...but as soon as I am absorbed in knowledge, I am blissfully happy and nothing can assail me.
     From: Arthur Schopenhauer (Manuscript remains [1855], I p.137), quoted by Peter B. Lewis - Schopenhauer 4
     A reaction: So the source of his pessimism is subjection to his own will. However, since becoming absorbed in knowledge is an easy task for a scholar, he has little to grumble about. Nietzsche mocked the great pessimist for playing the flute every day.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / b. Rational ethics
To deduce morality from reason is blasphemy, because it is holy, and far above reason [Schopenhauer]
     Full Idea: To deduce from reason [Vernunft] the moral element in conduct is blasphemy. In this element there is expressed the better consciousness which lies far above all reason. expresses itself in conduct as holiness, and is the true salvation of the world.
     From: Arthur Schopenhauer (Manuscript remains [1855], I p.47), quoted by Peter B. Lewis - Schopenhauer 3
     A reaction: Aimed at Kant. Only Plato could inspire a non-religious person to write about morality is such terms. Maybe also the stoic ideal of beautiful deeds (given the supreme value Schopenhauer placed on the arts).