11 ideas
| 3035 | Dialectic involves conversations with short questions and brief answers [Diog. Laertius] |
| Full Idea: Dialectic is when men converse by putting short questions and giving brief answers to those who question them. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 3.1.52) |
| 1816 | Sceptics say demonstration depends on self-demonstrating things, or indemonstrable things [Diog. Laertius] |
| Full Idea: Sceptics say that every demonstration depends on things which demonstrates themselves, or on things which can't be demonstrated. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 9.Py.11) | |
| A reaction: This refers to two parts of Agrippa's Trilemma (the third being that demonstration could go on forever). He makes the first option sound very rationalist, rather than experiential. |
| 1819 | Scepticism has two dogmas: that nothing is definable, and every argument has an opposite argument [Diog. Laertius] |
| Full Idea: Sceptics actually assert two dogmas: that nothing should be defined, and that every argument has an opposite argument. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 9.Py.11) |
| 3064 | When sceptics say that nothing is definable, or all arguments have an opposite, they are being dogmatic [Diog. Laertius] |
| Full Idea: When sceptics say that they define nothing, and that every argument has an opposite argument, they here give a positive definition, and assert a positive dogma. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 9.11.11) |
| 1556 | By nature people are close to one another, but culture drives them apart [Hippias] |
| Full Idea: I regard you all as relatives - by nature, not by convention. By nature like is akin to like, but convention is a tyrant over humankind and often constrains people to act contrary to nature. | |
| From: Hippias (fragments/reports [c.430 BCE]), quoted by Plato - Protagoras 337c8 |
| 3033 | Induction moves from some truths to similar ones, by contraries or consequents [Diog. Laertius] |
| Full Idea: Induction is an argument which by means of some admitted truths establishes naturally other truths which resemble them; there are two kinds, one proceeding from contraries, the other from consequents. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 3.1.23) |
| 22371 | Determinism threatens free will if actions can be causally traced to external factors [Foot] |
| Full Idea: The determinism which worries the defender of free will is that if human action is subject to a universal law of causation, there will be for any action a set of sufficient conditions which can be traced back to factors outside the control of the agent. | |
| From: Philippa Foot (Free Will as Involving Determinism [1957], p.63) | |
| A reaction: She draws on Russell for this, but neither of them mention whether the causation is physical. Free will seems to imply non-physical causation. |
| 22372 | Not all actions need motives, but it is irrational to perform troublesome actions with no motive [Foot] |
| Full Idea: We do not expect that everything a rational man does should be done with a motive, ...but we do expect a man to have a motive for many things that he does, and would count anyone who constantly performed troublesome actions without a motive as irrational. | |
| From: Philippa Foot (Free Will as Involving Determinism [1957], p.66) | |
| A reaction: Interestng, because the assessment of whether someone is 'rational' therefore needs a criterion for when a motive seems required and when not. 'Significant' actions need a motive? |
| 1838 | Cyrenaic pleasure is a motion, but Epicurean pleasure is a condition [Diog. Laertius] |
| Full Idea: Cyrenaics place pleasure wholly in motion, whereas Epicurus admits it as a condition. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 10.28) | |
| A reaction: Not a distinction we meet in modern discussions. Do events within the mind count as 'motion'? If so, these two agree. If not, I'd vote for Epicurus. |
| 1769 | Cynics believe that when a man wishes for nothing he is like the gods [Diog. Laertius] |
| Full Idea: Cynics believe that when a man wishes for nothing he is like the gods. | |
| From: Diogenes Laertius (Lives of Eminent Philosophers [c.250], 6.Men.3) |
| 22373 | People can act out of vanity without being vain, or even vain about this kind of thing [Foot] |
| Full Idea: It makes sense to say that a man acts out of vanity on a particular occasion although he is not in general vain, or even vain about this kind of thing. | |
| From: Philippa Foot (Free Will as Involving Determinism [1957], p.69) | |
| A reaction: Aristotle tells us that virtues and vices are habits, and also have an intellectual component, implying that the person believes in that sort of behaviour. Anyone can have 'a little moment of vanity'. |