Combining Texts

All the ideas for 'works (all lost)', 'Phil of Mathematics and Natural Science' and 'Elements of Geometry'

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19 ideas

1. Philosophy / D. Nature of Philosophy / 6. Hopes for Philosophy
If all laws were abolished, philosophers would still live as they do now [Aristippus elder]
2. Reason / E. Argument / 6. Conclusive Proof
Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / c. Derivations rules of PC
If you pick an arbitrary triangle, things proved of it are true of all triangles [Euclid, by Lemmon]
6. Mathematics / A. Nature of Mathematics / 2. Geometry
Euclid's geometry is synthetic, but Descartes produced an analytic version of it [Euclid, by Resnik]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
An assumption that there is a largest prime leads to a contradiction [Euclid, by Brown,JR]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / m. One
A unit is that according to which each existing thing is said to be one [Euclid]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Postulate 2 says a line can be extended continuously [Euclid, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Euclid relied on obvious properties in diagrams, as well as on his axioms [Potter on Euclid]
Euclid's parallel postulate defines unique non-intersecting parallel lines [Euclid, by Friend]
Euclid needs a principle of continuity, saying some lines must intersect [Shapiro on Euclid]
Euclid says we can 'join' two points, but Hilbert says the straight line 'exists' [Euclid, by Bernays]
Modern geometries only accept various parts of the Euclid propositions [Russell on Euclid]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / b. Greek arithmetic
Euclid's common notions or axioms are what we must have if we are to learn anything at all [Euclid, by Roochnik]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / h. Against ethics
Only the Cyrenaics reject the idea of a final moral end [Aristippus elder, by Annas]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
The road of freedom is the surest route to happiness [Aristippus elder, by Xenophon]
23. Ethics / A. Egoism / 3. Cyrenaic School
People who object to extravagant pleasures just love money [Aristippus elder, by Diog. Laertius]
Pleasure is the good, because we always seek it, it satisfies us, and its opposite is the most avoidable thing [Aristippus elder, by Diog. Laertius]
25. Social Practice / D. Justice / 3. Punishment / b. Retribution for crime
Errors result from external influence, and should be corrected, not hated [Aristippus elder, by Diog. Laertius]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / e. Anti scientific essentialism
The limit of science is isomorphism of theories, with essences a matter of indifference [Weyl]