display all the ideas for this combination of philosophers
15 ideas
| 6561 | A thing cannot be both in and not-in the same thing (at a given time) [Aristotle] |
| Full Idea: It is impossible for the same thing at the same time both to be-in and not to be-in the same thing in the same respect. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1005b19) | |
| A reaction: Aristotle is really discussing non-contradiction here, but this formulation is very close to Leibniz's Law (that two identical things must have identical properties). |
| 1601 | The most certain basic principle is that contradictories can't be true at the same time [Aristotle] |
| Full Idea: The most certain of all basic principles is that contradictory propositions are not true at the same time. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1011b13) | |
| A reaction: Principle of Noncontradiction |
| 11282 | Aristotle does not take the principle of non-contradiction for granted [Aristotle, by Politis] |
| Full Idea: Aristotle goes to great lengths to defend the principle of non-contradiction, and does not at all think that it is obviously true. | |
| From: report of Aristotle (Metaphysics [c.324 BCE], logic) by Vassilis Politis - Aristotle and the Metaphysics 5.1 |
| 23917 | Contrary statements can both be reasonable, if they are meant in two different ways [Aristotle] |
| Full Idea: Contrary things can be reasonably held …because the contrary positions will stand if what is said is true in one way, but not true in another. | |
| From: Aristotle (Eudemian Ethics [c.333 BCE], 1235b17) | |
| A reaction: My strategy here is to clarify the unambiguous underlying propositions which are being expressed. There will then be either agreement, or flat contradiction. |
| 11281 | We cannot say that one thing both is and is not a man [Aristotle] |
| Full Idea: It is not possible to say truly at the same time that the same thing both is and is not a man. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1006b33) |
| 1602 | For Aristotle predication is regulated by Non-Contradiction, because underlying stability is essential [Roochnik on Aristotle] |
| Full Idea: The Principle of Noncontradiction is for Aristotle the ultimate regulator of predication. In order for any predication to be significant it must refer to something definite and stable. | |
| From: comment on Aristotle (Metaphysics [c.324 BCE], 1011b13) by David Roochnik - The Tragedy of Reason p.152 |
| 4333 | Contraries are by definition as far distant as possible from one another [Aristotle] |
| Full Idea: Contraries are by definition as far distant as possible from one another. | |
| From: Aristotle (Nicomachean Ethics [c.334 BCE], 1108b33) | |
| A reaction: A nice concept and definition. Note that it is being used about ethics (the mean), not just about pure logic or mathematics. |
| 1697 | The contrary of good is bad, but the contrary of bad is either good or another evil [Aristotle] |
| Full Idea: What is contrary to a good thing is necessarily bad, as we see with health and sickness. But the contrary of bad is sometimes good, sometimes not, as we see with excess, opposed by both deficiency and moderation. | |
| From: Aristotle (Categories [c.331 BCE], 13b36) |
| 1698 | Both sides of contraries need not exist (as health without sickness, white without black) [Aristotle] |
| Full Idea: With contraries it is not necessary if one exists for the other to exist too, for if everyone were well health would exist but not sickness, and if everything were white whiteness would exist but not black. | |
| From: Aristotle (Categories [c.331 BCE], 14a06) |
| 1708 | In "Callias is just/not just/unjust", which of these are contraries? [Aristotle] |
| Full Idea: Take, for example, "Callias is just", "Callias is not just", and "Callias is unjust"; which of these are contraries? | |
| From: Aristotle (On Interpretation [c.330 BCE], 23a31) |
| 24052 | From one thing alone we can infer its contrary [Aristotle] |
| Full Idea: One member of a pair of contraries is sufficient to discern both itself and its opposite. | |
| From: Aristotle (De Anima [c.329 BCE], 411a02) | |
| A reaction: This obviously requires prior knowledge of what the opposite is. He says you can infer the crooked from the straight. You can hardly use light in isolation to infer dark [see DA 418b17]. What's the opposite of a pig? |
| 1684 | Two falsehoods can be contrary to one another [Aristotle] |
| Full Idea: There are falsehoods which are contrary to one another and cannot be the case together e.g. that a man is a horse or a cow. | |
| From: Aristotle (Posterior Analytics [c.327 BCE], 88a29) |
| 608 | There is no middle ground in contradiction, but there is in contrariety [Aristotle] |
| Full Idea: With contradiction there can be no intermediate state, whereas with contrariety there can be. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1055b02) |
| 627 | If everything is made of opposites, are the opposed things made of opposites? [Aristotle] |
| Full Idea: If all things are composed of opposites, how can the things of which the opposites are made be composed of opposites? | |
| From: Aristotle (Metaphysics [c.324 BCE], 1075a23) | |
| A reaction: A nice warning against being too simplistic in metaphysics. |
| 628 | Not everything is composed of opposites; what, for example, is the opposite of matter? [Aristotle] |
| Full Idea: All things are not composed of opposites, because matter is not the opposite of anything. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1075a28) | |
| A reaction: A nice counterexample |