22 ideas
| 1642 | We must fight fiercely for knowledge, understanding and intelligence [Plato] |
| Full Idea: We need to use every argument we can to fight against anyone who does away with knowledge, understanding, and intelligence, but at the same time asserts anything at all about anything. | |
| From: Plato (The Sophist [c.359 BCE], 249c) | |
| A reaction: Thus showing that reason is only central if you want to put a high value on it? |
| 1645 | The desire to split everything into its parts is unpleasant and unphilosophical [Plato] |
| Full Idea: To try to set apart everything from everything is not only especially jangling, but it is the mark of someone altogether unmusical and unphilosophic. | |
| From: Plato (The Sophist [c.359 BCE], 259e) |
| 287 | Good analysis involves dividing things into appropriate forms without confusion [Plato] |
| Full Idea: It takes expertise in dialectic to divide things by kinds and not to think that the same form is a different one or that a different form is the same. | |
| From: Plato (The Sophist [c.359 BCE], 253d) |
| 1644 | Dialectic should only be taught to those who already philosophise well [Plato] |
| Full Idea: The dialectical capacity - you won't give it to anyone else, I suspect, except to whoever philosophises purely and justly. | |
| From: Plato (The Sophist [c.359 BCE], 253e) |
| 20478 | In discussion a person's opinions are shown to be in conflict, leading to calm self-criticism [Plato] |
| Full Idea: They collect someone's opinions together during the discussion, put them side by side, and show that they conflict with each other at the same time on the same subjects.... The person sees this, gets angry at themselves, and calmer towards others. | |
| From: Plato (The Sophist [c.359 BCE], 230b) | |
| A reaction: He goes on to say that the process is like a doctor purging a patient of internal harms. If anyone talks for long enough (even a good philosopher), their opinions will probably be seen to be in conflict. But which opinions do you abandon? |
| 11278 | What does 'that which is not' refer to? [Plato] |
| Full Idea: What should the name 'that which is not' be applied to? | |
| From: Plato (The Sophist [c.359 BCE], 237c) | |
| A reaction: This leads into a discussion of the problem, in The Sophist. It became a large issue when modern logic was being developed by Frege and Russell. |
| 1643 | If statements about non-existence are logically puzzling, so are statements about existence [Plato] |
| Full Idea: When the question was put to us as to the name of 'that which is not', to whatever one must apply it, we got stuck in every kind of perplexity. Are we now in any less perplexity about 'that which is'? | |
| From: Plato (The Sophist [c.359 BCE], 250d) | |
| A reaction: Nice. This precapitulates the whole story of modern philosophy of language. What started as a nagging doubt about reference to non-existents ends as bewilderment about everything we say. |
| 7022 | To be is to have a capacity, to act on other things, or to receive actions [Plato] |
| Full Idea: A thing really is if it has any capacity, either by nature to do something to something else or to have even the smallest thing done to it by the most trivial thing, even if it only happens once. I'll define those which are as nothing other than capacity. | |
| From: Plato (The Sophist [c.359 BCE], 247e) | |
| A reaction: If philosophy is footnotes to Plato, this should be the foundational remark in all discussions of existence (though Parmenides might claim priority). It seems to say 'to be is to have a causal role (active or passive)'. It also seems essentialist. |
| 1641 | Some alarming thinkers think that only things which you can touch exist [Plato] |
| Full Idea: One group drags everything down to earth, insisting that only what offers tangible contact is, since they define being as the same as body, despising anyone who says that something without a body is. These are frightening men. | |
| From: Plato (The Sophist [c.359 BCE], 246b) |
| 10784 | Whenever there's speech it has to be about something [Plato] |
| Full Idea: Whenever there's speech it has to be about something. It's impossible for it not to be about something. | |
| From: Plato (The Sophist [c.359 BCE], 262e) | |
| A reaction: [Quoted by Marcus about ontological commitment] The interesting test case would be speech about the existence of circular squares. |
| 16122 | Good thinkers spot forms spread through things, or included within some larger form [Plato] |
| Full Idea: It takes dialectic to divide things by kinds...such a person can discriminate a single form spread through a lot of separate things…and forms included in a single outside form…or a form connected as a unit through many wholes. | |
| From: Plato (The Sophist [c.359 BCE], 253d) | |
| A reaction: [compressed] This is very helpful in indicating the complex structure of the Forms that Plato envisages. If you talk of the meanings of words (other than names), though, it comes to the same thing. Wise people fully understand their language. |
| 10422 | The not-beautiful is part of the beautiful, though opposed to it, and is just as real [Plato] |
| Full Idea: So 'the not beautiful' turns out to be ..both marked off within one kind of those that are, and also set over against one of those that are, ..and the beautiful is no more a being than the not beautiful. | |
| From: Plato (The Sophist [c.359 BCE], 257d) | |
| A reaction: [dialogue eliminated] This is a highly significant passage, for two reasons. It suggests that the Form of the beautiful can have parts, and also that the negations of Forms are Forms themselves (both of which come as a surprise). |
| 15855 | If we see everything as separate, we can then give no account of it [Plato] |
| Full Idea: To dissociate each thing from everything else is to destroy totally everything there is to say. The weaving together of forms is what makes speech [logos] possible for us. | |
| From: Plato (The Sophist [c.359 BCE], 259e) | |
| A reaction: This I take to be the lynchpin of metaphysics. We are forced to see the world in a way which enables us to give some sort of account of it. Our metaphysics is 'inference to the best logos'. |
| 13856 | Conditionals are truth-functional, but we must take care with misleading ones [Grice, by Edgington] |
| Full Idea: Grice argued that the truth-functional account of conditionals can withstand objections, provided that we are careful to distinguish the false from the misleadingly true. | |
| From: report of H. Paul Grice (Logic and Conversation [1975]) by Dorothy Edgington - Do Conditionals Have Truth Conditions? 2 |
| 8948 | The odd truth table for material conditionals is explained by conversational conventions [Grice, by Fisher] |
| Full Idea: According to Grice, it is the rules that govern conversation beyond the merely logical that account for the counter-intuitiveness of the truth table for the material conditional. | |
| From: report of H. Paul Grice (Logic and Conversation [1975]) by Jennifer Fisher - On the Philosophy of Logic 8.I | |
| A reaction: There is a conversational rule which says that replies should normally relevant to context. It would be nice if logical implications were also relevant to context. |
| 13767 | Conditionals might remain truth-functional, despite inappropriate conversational remarks [Edgington on Grice] |
| Full Idea: Grice defended the truth-functional account of conditionals, noting the gap between what we are justified in believing and what is appropriate to say. .But the problem arises at the level of belief, not at the level of inappropriate conversational remarks | |
| From: comment on H. Paul Grice (Logic and Conversation [1975]) by Dorothy Edgington - Conditionals 17.1.3 |
| 14277 | A person can be justified in believing a proposition, though it is unreasonable to actually say it [Grice, by Edgington] |
| Full Idea: Grice drew attention to situations in which a person is justified in believing a proposition, which would nevertheless by an unreasonable thing for the person to say, in normal circumstances. I think he is right about disjunction and negated conjunctions. | |
| From: report of H. Paul Grice (Logic and Conversation [1975]) by Dorothy Edgington - Conditionals (Stanf) 2.4 | |
| A reaction: Edgington considers Grice's ideas of implicature as of permanent value, especially as a clarification of 1950s ordinary language philosophy. |
| 1637 | A soul without understanding is ugly [Plato] |
| Full Idea: The soul that lacks understanding must be set down as ugly. | |
| From: Plato (The Sophist [c.359 BCE], 228d) | |
| A reaction: The teleological view of things understands their nature in things of their perfection. and the essence of beauty is perfection. It is the mind's nature to know. Failing to know is as ugly as allowing your crops to die. |
| 1636 | Wickedness is an illness of the soul [Plato] |
| Full Idea: Wickedness is a sedition and illness of the soul. | |
| From: Plato (The Sophist [c.359 BCE], 228b) |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
| From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
| A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
| 1638 | Didactic education is hard work and achieves little [Plato] |
| Full Idea: With a lot of effort the admonitory species of education accomplishes little. | |
| From: Plato (The Sophist [c.359 BCE], 230a) |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
| Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
| From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
| A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |