23 ideas
| 8378 | Philosophers usually learn science from each other, not from science [Russell] |
| 7807 | The laws of thought are true, but they are not the axioms of logic [Bolzano, by George/Van Evra] |
| 3035 | Dialectic involves conversations with short questions and brief answers [Diog. Laertius] |
| 9618 | Bolzano wanted to reduce all of geometry to arithmetic [Bolzano, by Brown,JR] |
| 9830 | Bolzano began the elimination of intuition, by proving something which seemed obvious [Bolzano, by Dummett] |
| 17265 | Philosophical proofs in mathematics establish truths, and also show their grounds [Bolzano, by Correia/Schnieder] |
| 8375 | 'Necessary' is a predicate of a propositional function, saying it is true for all values of its argument [Russell] |
| 9185 | Bolzano wanted to avoid Kantian intuitions, and prove everything that could be proved [Bolzano, by Dummett] |
| 1816 | Sceptics say demonstration depends on self-demonstrating things, or indemonstrable things [Diog. Laertius] |
| 1819 | Scepticism has two dogmas: that nothing is definable, and every argument has an opposite argument [Diog. Laertius] |
| 3064 | When sceptics say that nothing is definable, or all arguments have an opposite, they are being dogmatic [Diog. Laertius] |
| 3033 | Induction moves from some truths to similar ones, by contraries or consequents [Diog. Laertius] |
| 22276 | Bolzano saw propositions as objective entities, existing independently of us [Bolzano, by Potter] |
| 17264 | Propositions are abstract structures of concepts, ready for judgement or assertion [Bolzano, by Correia/Schnieder] |
| 12232 | A 'proposition' is the sense of a linguistic expression, and can be true or false [Bolzano] |
| 12233 | The ground of a pure conceptual truth is only in other conceptual truths [Bolzano] |
| 1838 | Cyrenaic pleasure is a motion, but Epicurean pleasure is a condition [Diog. Laertius] |
| 1769 | Cynics believe that when a man wishes for nothing he is like the gods [Diog. Laertius] |
| 4396 | The law of causality is a source of confusion, and should be dropped from philosophy [Russell] |
| 8376 | If causes are contiguous with events, only the last bit is relevant, or the event's timing is baffling [Russell] |
| 8380 | Striking a match causes its igniting, even if it sometimes doesn't work [Russell] |
| 8379 | In causal laws, 'events' must recur, so they have to be universals, not particulars [Russell] |
| 8381 | The constancy of scientific laws rests on differential equations, not on cause and effect [Russell] |