17 ideas
| 9108 | From an impossibility anything follows [William of Ockham] |
| Full Idea: From an impossibility anything follows ('quod ex impossibili sequitur quodlibet'). | |
| From: William of Ockham (Summa totius logicae [1323], III.c.xxxvi) | |
| A reaction: The hallmark of a true logician, I suspect, is that this opinion is really meaningful and important to them. They yearn to follow the logic wherever it leads. Common sense would seem to say that absolutely nothing follows from an impossibility. |
| 9107 | A proposition is true if its subject and predicate stand for the same thing [William of Ockham] |
| Full Idea: If in the proposition 'This is an angel' subject and predicate stand for the same thing, the proposition is true. | |
| From: William of Ockham (Summa totius logicae [1323], II.c.ii) | |
| A reaction: An interesting statement of what looks like a correspondence theory, employing the idea that both the subject and the predicate have a reference. I think Frege would say that 'x is an angel' is unsaturated, and so lacks reference. |
| 16300 | Ockham had an early axiomatic account of truth [William of Ockham, by Halbach] |
| Full Idea: Theories structurally very similar to axiomatic compositional theories of truth can be found in Ockham's 'Summa Logicae'. | |
| From: report of William of Ockham (Summa totius logicae [1323]) by Volker Halbach - Axiomatic Theories of Truth 3 |
| 9106 | The word 'every' only signifies when added to a term such as 'man', referring to all men [William of Ockham] |
| Full Idea: The syncategorematic word 'every' does not signify any fixed thing, but when added to 'man' it makes the term 'man' stand for all men actually. | |
| From: William of Ockham (Summa totius logicae [1323], I.c.iv) | |
| A reaction: Although quantifiers may have become a part of formal logic with Frege, their importance is seen from Aristotle onwards, and it is clearly a key part of William's understanding of logic. |
| 9113 | Just as unity is not a property of a single thing, so numbers are not properties of many things [William of Ockham] |
| Full Idea: Number is nothing but the actual numbered things themselves. Hence just as unity is not an accident added to the thing which is one, so number is not an accident of the things which are numbered. | |
| From: William of Ockham (Summa totius logicae [1323], I.c.xliv) | |
| A reaction: [William does not necessarily agree with this view] It strikes me as a key point here that any account of the numbers had better work for 'one', though 'zero' might be treated differently. Some people seem to think unity is a property of things. |
| 9110 | The words 'thing' and 'to be' assert the same idea, as a noun and as a verb [William of Ockham] |
| Full Idea: The words 'thing' and 'to be' (esse) signify one and the same thing, but the one in the manner of a noun and the other in the manner of a verb. | |
| From: William of Ockham (Summa totius logicae [1323], III,II,c,xxvii) | |
| A reaction: Well said - as you would expect from a thoroughgoing nominalist. I would have thought that this was the last word on the subject of Being, thus rendering any need for me to read Heidegger quite superfluous. Or am I missing something? |
| 15388 | Universals are single things, and only universal in what they signify [William of Ockham] |
| Full Idea: Every universal is one particular thing and it is not a universal except in its signification, in its signifying many thing. | |
| From: William of Ockham (Summa totius logicae [1323]), quoted by Claude Panaccio - Medieval Problem of Universals 'William' | |
| A reaction: Sounds as if William might have liked tropes. It seems to leave the problem unanswered (the 'ostrich' problem?). How are they able to signify in this universal way, if each thing is just distinct and particular? |
| 9109 | If essence and existence were two things, one could exist without the other, which is impossible [William of Ockham] |
| Full Idea: If essence and existence were two things, then no contradiction would be involved if God preserved the essence of a thing in the world without its existence, or vice versa, its existence without its essence; both of which are impossible. | |
| From: William of Ockham (Summa totius logicae [1323], III,II,c,xxvii) | |
| A reaction: Not that William is using the concept of a supreme mind as a tool in argument. His denial of essence as something separable is presumably his denial of the Aristotelian view of universals, as well as of the Platonic view. |
| 9105 | Some concepts for propositions exist only in the mind, and in no language [William of Ockham] |
| Full Idea: Conceptual terms and the propositions formed by them are those mental words which do not belong to any language; they remain only in the mind and cannot be uttered exteriorly, though signs subordinated to these can be exteriorly uttered. | |
| From: William of Ockham (Summa totius logicae [1323], I.c.i) | |
| A reaction: [He cites Augustine] A glimmer of the idea of Mentalese, and is probably an integral part of any commitment to propositions. Quine would hate it, but I like it. Logicians seem to dislike anything that cannot be articulated, but brains are like that. |
| 21103 | Moral questions can only be decided by common opinion [Hume] |
| Full Idea: Though an appeal to general opinion may justly, in the speculative sciences of metaphysics, natural philosophy or astronomy, be deemed unfair, yet in all questions with regard to morals there is really no other standard for deciding controversies. | |
| From: David Hume (Of the original contract [1741], p.291) | |
| A reaction: Surely this is too pessimistic. Common opinion decided to burn people to death for being witches. Common opinion may usually win, but there must sometimes be good grounds for resisting it. |
| 21099 | People must have agreed to authority, because they are naturally equal, prior to education [Hume] |
| Full Idea: When we consider how nearly equal all men are in their bodily force, and even in their mental powers and faculties, till cultivated by education, ...then nothing but their own consent could at first associate them together, and subject them to authority. | |
| From: David Hume (Of the original contract [1741], p.276) | |
| A reaction: This doesn't sound very convincing. Some people are much better suited than others to training and education. Men vary enormously in size. |
| 21100 | The idea that society rests on consent or promises undermines obedience [Hume] |
| Full Idea: Were you to preach in most parts of the world that political connections are founded altogether on voluntary consent or a mutual promise, the magistrate would soon imprison you as seditious for loosening the ties of obedience. | |
| From: David Hume (Of the original contract [1741], p.278) | |
| A reaction: He cites obedience as the prime civic virtue, because the law can't operate without it. He doesn't seem to consider the limiting cases of obedience, which makes him essentially a conservative. |
| 20495 | We no more give 'tacit assent' to the state than a passenger carried on board a ship while asleep [Hume] |
| Full Idea: [If we give 'tacit' assent to the state] ...we may as well assert that a man, by remaining in a vessel, freely consents to the dominion of the master, though he was carried aboard while asleep. | |
| From: David Hume (Of the original contract [1741], p.283) | |
| A reaction: We should probably drop the whole idea that we give assent to the state. We are stuck with a state, and a few of us can escape, if it seems important enough, but most of us have no choice. He hope to assent to the controllers of the state. |
| 21101 | The people would be amazed to learn that government arises from their consent [Hume] |
| Full Idea: When we assert that all lawful government arises from the consent of the people, we certainly do them a great deal more honour than they deserve, or even expect or desire from us. | |
| From: David Hume (Of the original contract [1741], p.285) | |
| A reaction: Hume has no interest in the purely abstract idea of a contract, and scorns Locke's idea of tacit consent to government. I assume he would dismiss Rawls as unrealistic theorising. Hume loves peace, and is alarmed by change. |
| 6703 | Poor people lack the knowledge or wealth to move to a different state [Hume] |
| Full Idea: Can we seriously say, that a poor peasant or artisan has a free choice to leave his country, when he knows no foreign language or manners, and lives, from day to day, by the small wages that he acquires? | |
| From: David Hume (Of the original contract [1741], p.283) | |
| A reaction: Of course, in the nineteenth century the Scottish poor did, going to America, which welcomed the poor, and spoke English. Hume's point is the right reply to anyone who says 'If you don't like it, go elsewhere'. Also 'No! Change it!' |
| 21102 | We all know that the history of property is founded on injustices [Hume] |
| Full Idea: Reason tells us that there is no property in durable objects, such as land or houses, when carefully examined in passing from hand to hand, but must, in some period, have been founded on fraud and injustice. | |
| From: David Hume (Of the original contract [1741], p.288) | |
| A reaction: A prime objection to Nozick, who fantasises about an initial position of just ownership, which can then be the subject of just contracts. In 1866 thousands of white people were granted land in the USA, but not a single black freed slave got anything. |
| 2116 | The concept of an existing thing must contain more than the concept of a non-existing thing [Leibniz] |
| Full Idea: There must be more in the concept of a thing which exists than in that of one which does not exist. | |
| From: Gottfried Leibniz (On the Principles of Indiscernibles [1696], p.134) |