49 ideas
| 17697 | The existence of an arbitrarily large number refutes the idea that numbers come from experience [Hilbert] |
| Full Idea: The standpoint of pure experience seems to me to be refuted by the objection that the existence, possible or actual, of an arbitrarily large number can never be derived through experience, that is, through experiment. | |
| From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.130) | |
| A reaction: Alternatively, empiricism refutes infinite numbers! No modern mathematician will accept that, but you wonder in what sense the proposed entities qualify as 'numbers'. |
| 17698 | Logic already contains some arithmetic, so the two must be developed together [Hilbert] |
| Full Idea: In the traditional exposition of the laws of logic certain fundamental arithmetic notions are already used, for example in the notion of set, and to some extent also of number. Thus we turn in a circle, and a partly simultaneous development is required. | |
| From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.131) | |
| A reaction: If the Axiom of Infinity is meant, it may be possible to purge the arithmetic from the logic. Then the challenge to derive arithmetic from it becomes rather tougher. |
| 458 | Nothing could come out of nothing, and existence could never completely cease [Empedocles] |
| Full Idea: From what in no wise exists, it is impossible for anything to come into being; for Being to perish completely is incapable of fulfilment and unthinkable. | |
| From: Empedocles (fragments/reports [c.453 BCE], B012), quoted by Anon (Lyc) - On Melissus 975b1-4 |
| 5112 | Empedocles says things are at rest, unless love unites them, or hatred splits them [Empedocles, by Aristotle] |
| Full Idea: Empedocles claims that things are alternately changing and at rest - that they are changing whenever love is creating a unity out of plurality, or hatred is creating plurality out of unity, and they are at rest in the times in between. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Physics 250b26 | |
| A reaction: I suppose one must say that this an example of Ruskin's 'pathetic fallacy' - reading human emotions into the cosmos. Being constructive little creatures, we think goodness leads to construction. I'm afraid Empedocles is just wrong. |
| 13209 | There is no coming-to-be of anything, but only mixing and separating [Empedocles, by Aristotle] |
| Full Idea: Empedocles says there is no coming-to-be of anything, but only a mingling and a divorce of what has been mingled. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314b08 | |
| A reaction: Aristotle comments that this prevents Empedocleans from distinguishing between superficial alteration and fundamental change of identity. Presumably, though, that wouldn't bother them. |
| 457 | Substance is not created or destroyed in mortals, but there is only mixing and exchange [Empedocles] |
| Full Idea: There is no creation of substance in any one of mortal existence, nor any end in execrable death, but only mixing and exchange of what has been mixed. | |
| From: Empedocles (fragments/reports [c.453 BCE], B008), quoted by Plutarch - 74: Reply to Colotes 1111f | |
| A reaction: also Aristotle 314b08 |
| 462 | One vision is produced by both eyes [Empedocles] |
| Full Idea: One vision is produced by both eyes | |
| From: Empedocles (fragments/reports [c.453 BCE], B088), quoted by Strabo - works 8.364.3 |
| 22765 | Wisdom and thought are shared by all things [Empedocles] |
| Full Idea: Wisdom and power of thought, know thou, are shared in by all things. | |
| From: Empedocles (fragments/reports [c.453 BCE]), quoted by Sextus Empiricus - Against the Logicians (two books) II.286 | |
| A reaction: Sextus quotes this, saying that it is 'still more paradoxical', and that it explicitly includes plants. This may mean that Empedocles was not including inanimate matter. |
| 1524 | For Empedocles thinking is almost identical to perception [Empedocles, by Theophrastus] |
| Full Idea: Empedocles assumes that thinking is either identical to or very similar to sense-perception. | |
| From: report of Empedocles (fragments/reports [c.453 BCE], A86) by Theophrastus - On the Senses 9 | |
| A reaction: Not to be sniffed at. We can, of course, control our thinking (though we can't control the controller) and we contemplate abstractions, but that might be seen as a sort of perception. Vision is not as visual as we think. |
| 23590 | Criminal responsibility can be fully assigned to each member of a group [Walzer] |
| Full Idea: It is a feature of criminal responsibility that it can be distributed without being divided. We can, that is, blame more than one person for a particular act without splitting up the blame we assign. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 19) | |
| A reaction: How far can this extend? To a large violent mob? To an entire nation? In court the responsibility is usually adjusted in the sentencing, rather than in the initial verdict. |
| 23578 | Double Effect needs a double intention - to achieve the good, and minimise the evil [Walzer] |
| Full Idea: Double effect is defensible, I want to argue, only when the two outcomes are the product of a double intention - that 'good' be achieved, and that the foreseeable evil be reduced as far as possible. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 09) | |
| A reaction: A good proposal, I think. We have to accept evil side effects sometimes, but it is immoral to pursue some good 'whatever the cost'. |
| 23564 | Deep ethical theory is very controversial, but we have to live with higher ethical practice [Walzer] |
| Full Idea: The substructure of the ethical world is a matter of deep and unending controversy, Meanwhile, however, we are living in the superstructure. | |
| From: Michael Walzer (Just and Unjust Wars [1977], Pref) | |
| A reaction: This may be the best approach to ethics. Nearly all applied ethics takes the common sense consensus on values for granted. Personally I think that is because the substructure is the obvious success and failure of human functioning. |
| 552 | Empedocles said good and evil were the basic principles [Empedocles, by Aristotle] |
| Full Idea: Empedocles was the first to give evil and good as principles. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Metaphysics 985a | |
| A reaction: Once you start to think that good and evil will only matter if they have causal powers, it is an easy step to the idea of a benevolent god, and a satanic anti-god. Otherwise the 'principles' could be ignored. |
| 23568 | If whole states possess rights, there can be social relations between states [Walzer] |
| Full Idea: If states possess rights more or less as individuals do, then it is possible to imagine a society among them more or less like the individuals. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 04) | |
| A reaction: The state's rights must derive from the people. Plots of land don't have rights. In some states the people are in conflict. It can't just be the government which represents the rights of the state. |
| 23571 | States can rightly pre-empt real and serious threats [Walzer] |
| Full Idea: States can use force in the face of threats of war, if there is a serious risk to territory or independence. They are then forced to fight, and are the victims of aggression. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 05) | |
| A reaction: [compressed] He uses this to justify Israeli pre-emptive strikes against Palestinians. I don't think his confident assertion of this principle is justified. It is open to massive abuse. There are, though, clearly situations where he is right. |
| 23572 | Just wars are self-defence, or a rightful intercession in another's troubles [Walzer] |
| Full Idea: Just wars may not be self-defence, if they are to help an independence struggle, or it is to save another country being invaded, or to prevent enslavement or massacre. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 06) | |
| A reaction: [summary] Modern wars support some examples of these, but also suggest that without a long-term plan, or an understanding of the country they are entering, such intercessions may worsen the situation. |
| 23581 | The aim of reprisals is to enforce the rules of war [Walzer] |
| Full Idea: The purpose of reprisals is not to win the war or prevent defeat, but simply to enforce the rules [of war]. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 13) | |
| A reaction: That may be wishful thinking, since reprisals are often vastly more ruthless than the original offence, and there is often injustice in the nature of the reprisals, since they cannot be precise. |
| 23582 | Reprisal is defensible, as an alternative to war [Walzer] |
| Full Idea: Reprisal is the first resort of force. It is an alternative to war, and that description is an important argument in its favour. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 13) | |
| A reaction: Enduring wrongs with dignity might be another alternative. Successful reprisals may be acceptable, but how do you assess their prospects? |
| 23588 | With nuclear weapons we have a permanent supreme emergency (which is unstable) [Walzer] |
| Full Idea: With nuclear weapons, supreme emergency has become a permanent condition. …[283] But supreme emergency is never a stable position. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 17) | |
| A reaction: The obvious instability of balanced mutual threat is a nuclear state which finds itself losing a war. |
| 23580 | States need not endure attacks passively, and successful reprisals are legitimate [Walzer] |
| Full Idea: Whenever there is some substantial chance of success, reprisals are the legitimate resort of a victim state; for no state can be required passively to endure attacks upon its citizens. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 13) | |
| A reaction: My concern is whether the reprisals have any direct connection to the attacks. They killed some of ours, so we will kill some of theirs is immoral. E.g. bombing Tripoli as reprisal for crashing the Lockerbie plane. |
| 23587 | Nuclear bombs are not for normal war; they undermine the 'just war', with a new morality [Walzer] |
| Full Idea: Nuclear weapons are not designed for war at all. …They explode the idea of a just war. They are the first technological innovations that are simply not encompassable within the familiar moral world. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 17) | |
| A reaction: A nuclear war can hardly lead to normal victory, if it destroys the thing you are trying to conquer. It is like bringing a machine gun to a boxing match. |
| 23567 | Even non-violent intrusive acts between states count as aggression, if they justify resistance [Walzer] |
| Full Idea: Every violation of an independent state is called aggression, which fails to differentiate between a seizure or imposition, and an actual conquest. …But what they have in common is that all aggressive acts justify forceful resistance. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 04) | |
| A reaction: [compressed] Walzer concedes that this makes 'aggression' rather imprecise, and small acts can be used as an excuse for desired violent resistance. Each entrant in August 1914 seems to have had a slightly different motive. |
| 23570 | The only good reason for fighting is in defence of rights [Walzer] |
| Full Idea: The defence of rights is a reason for fighting. I want now to stress again, and finally, that it is the only reason. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 04) | |
| A reaction: Walzer states at the beginning, without discussion, that his moral assumptions are based on the notion of rights. This is tricky because rights are assigned by some people to other people, and claims of rights can be challenged. |
| 23573 | For moral reasons, a just war must be a limited war [Walzer] |
| Full Idea: Just wars are limited wars; there are moral reasons for the statesmen and soldiers who fight them to be prudent and realistic. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 07) | |
| A reaction: This is rather profound, I think. Watch closely the behaviour of the good guys when they are winning the war. In general, to know someone's moral principles, the best indicator is how they behave when they have power. |
| 23577 | Napoleon said 'I don't care about the deaths of a million men' [Walzer] |
| Full Idea: Napoleon said 'Soldiers are made to be killed. …I do not care a fig for the lives of a million men'. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 08) | |
| A reaction: [Two separate remarks attributed to Napoleon] He apparently often said things like this this later in his career. It strikes me as despicable, and anyone who still tries to present Napoleon as admirable should be ashamed. |
| 23593 | Jus ad bellum and Jus in bello are independent; unjust wars can be fought in a just way [Walzer] |
| Full Idea: Justice of war [ad bellum] and justice in war [in bello] are logically independent. It is perfectly possible for a just war to be fought unjustly, and for an unjust war to be fought in strict accordance with the rules. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 02) | |
| A reaction: The perfect decorum of an unjust firing squad might even make the crime worse. There is something chilling about an evil army conducting itself perfectly within the ethics of warfare. Better than the other thing, though. McMahan disagrees. |
| 23574 | The duties and moral status of loyal and obedient soldiers is the same in defence and aggression [Walzer] |
| Full Idea: The duties of individual soldiers …are precisely the same in wars of aggression and wars of defence. …The moral status of soldiers on both sides is very much the same; they are led to fight by their loyalty and their lawful obedience. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 08) | |
| A reaction: He excludes war crimes. This is the thesis which Jeff McMahan objects to. It would be very odd to think that mafiosi and the legitimate police were morally equal, because the former are loyal. We should all try hard to avoid supporting unjust causes. |
| 23575 | We can't blame soldiers for anything they do which clearly promotes victory [Walzer] |
| Full Idea: It would be difficult to condemn soldiers for anything they did in the course of a battle or a war that they honestly believed, and had good reason to believe, was necessary, or important, or simply useful in determining the outcome. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 08) | |
| A reaction: We can't blame unjust aggressors if their own lives are at stake, but what about in a surprise attack on the first day of the war (such as Pearl Harbour)? Or if they massacre the enemy with safe and overwhelming superiority? |
| 23584 | Rejecting Combatant Equality allows just soldiers to be harsher, even to the extreme [Walzer] |
| Full Idea: Objections to combatant equality appeal to a sliding scale of 'the more justice, the more right'. …It allows the justice of one's cause to make a difference in the way one fights. …The extreme says soldiers fightly justly can do anything that is useful. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 14) | |
| A reaction: This slippery slope fear seems to be Walzer's main argument in favour of the moral equality of combatants. See Jeff McMahan for the opposing view. |
| 23589 | Kidnapped sailors and volunteers have different obligations to the passengers [Walzer] |
| Full Idea: Soldiers may stand to civilians like the crew of a liner to its passengers, for whom they must risk their lives. …But would they be so bound if the sailors had been kidnapped? | |
| From: Michael Walzer (Just and Unjust Wars [1977], 19) | |
| A reaction: The point, I assume, is that a conscripted army does not have the same obligations as volunteers. I can't imagine that principle being accepted in an army which is a mixture of the two. |
| 23614 | Even aggressor soldiers are not criminals, so they have equal rights with their opponents [Walzer] |
| Full Idea: Soldiers fighting for an aggressor state are not themselves criminals: hence their war rights are the same as those of their opponents. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 08) | |
| A reaction: Walzer's main support for this is that opposing armies never regard one another as intrinsically criminal. It seems inevitable, though, that even the invaders themselves see that they are a bit more criminal than the defenders. |
| 23579 | Soldiers will only protect civilians if they feel safe from them [Walzer] |
| Full Idea: Soldiers must feel safe among civilians if civilians are ever to be safe from soldiers. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 11) | |
| A reaction: This is the great dilemma of any resistance movement. It is very easy for the soldiers to abuse their power, even if they do feel safe. Then what? |
| 23586 | What matters in war is unacceptable targets, not unacceptable weapons [Walzer] |
| Full Idea: The crucial distinction in the theory and practice of war is not between prohibited and acceptable weapons but between prohibited and acceptable targets. | |
| From: Michael Walzer (Just and Unjust Wars [1977], 17) | |
| A reaction: Walzer presents this idea as arising out of discussions about nuclear deterrence. Gas attacks were accepted in WW1 trenches, but modern gas attacks on civilians are a crime. Are nuclear attacks on strictly military targets OK? E.g a fleet. |
| 23591 | If the oppressor is cruel, nonviolence is either surrender, or a mere gesture [Walzer] |
| Full Idea: When one cannot count on the moral code of the oppressor, nonviolence is either a disguised form of surrender or a minimalist way of upholding communal values after a military defeat. | |
| From: Michael Walzer (Just and Unjust Wars [1977], Afterword) | |
| A reaction: The point is that ruthless conquerors may just kill the nonviolent, so it would achieve nothing. Nonviolence is only a plausible strategy in a fairly civilised world. Hard to disagree. |
| 23592 | We can only lead war towards peace if we firmly enforce the rules of war [Walzer] |
| Full Idea: We must begin by insisting upon the rules of war and by holding soldiers rigidly to the norms they set. The restraint of war is the beginning of peace. | |
| From: Michael Walzer (Just and Unjust Wars [1977], Afterword) | |
| A reaction: Last sentence of his book. Some cultures have a much greater tradition of ruthless cruelty than others, it seems. Most war ethics seems to concern how the good guys should respond to the bad guys (since the latter hardly care). |
| 589 | 'Nature' is just a word invented by people [Empedocles] |
| Full Idea: Nature is but a word of human framing. | |
| From: Empedocles (fragments/reports [c.453 BCE], B008), quoted by Aristotle - Metaphysics 1015a |
| 21823 | The principle of 'Friendship' in Empedocles is the One, and is bodiless [Empedocles, by Plotinus] |
| Full Idea: In Empedocles we have a dividing principle, 'Strife', set against 'Friendship' - which is the One and is to him bodiless, while the elements represent matter. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Plotinus - The Enneads 5.1.09 | |
| A reaction: The first time I've seen the principle of Love in Empedocles identified with the One of Parmenides. Plotinus is a trustworthy reporter, I think, because he was well read, and had access to lost texts. |
| 2680 | Empedocles said that there are four material elements, and two further creative elements [Empedocles, by Aristotle] |
| Full Idea: Empedocles holds that the corporeal elements are four, but that all the elements, including those which create motion, are six in number. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314a16 |
| 6002 | Empedocles says bone is water, fire and earth in ratio 2:4:2 [Empedocles, by Inwood] |
| Full Idea: Empedocles used numerical ratios to explain different kinds of matter; for example, bone is two parts water, four parts fire, two parts earth; and blood is an equal blend of all four elements. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Brad Inwood - Empedocles | |
| A reaction: Why isn't the ration 1:2:1? This presumably shows the influence of Pythagoras (who had also been based in Italy, like Empedocles), as well as that of the earlier naturalistic philosophers. It was a very good theory, though wrong. |
| 13207 | Fire, Water, Air and Earth are elements, being simple as well as homoeomerous [Empedocles, by Aristotle] |
| Full Idea: Empedocles says that Fire, Water, Air and Earth are four elements, and are thus 'simple' rather than flesh, bone and bodies which, like these, are 'homoeomeries'. | |
| From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314a26 | |
| A reaction: The translation is not quite clear. I take it that flesh and bone may look simple, because they are homoeomerous, but they are not really - but what is his evidence for that? Compare Idea 13208. |
| 459 | All change is unity through love or division through hate [Empedocles] |
| Full Idea: These elements never cease their continuous exchange, sometimes uniting under the influence of Love, so that all become One, at other times again moving apart through the hostile force of Hate. | |
| From: Empedocles (fragments/reports [c.453 BCE], B017), quoted by Simplicius - On Aristotle's 'Physics' 158.1- |
| 13218 | The elements combine in coming-to-be, but how do the elements themselves come-to-be? [Aristotle on Empedocles] |
| Full Idea: Empedocles says it is evident that all the other bodies down to the 'elements' have their coming-to-be and their passing-away: but it is not clear how the 'elements' themselves, severally in their aggregated masses, come-to-be and pass-away. | |
| From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325b20 | |
| A reaction: Presumably the elements are like axioms - and are just given. How do electrons and quarks come-to-be? |
| 13225 | Love and Strife only explain movement if their effects are distinctive [Aristotle on Empedocles] |
| Full Idea: It is not an adequate explanation to say that 'Love and Strife set things moving', unless the very nature of Love is a movement of this kind and the very nature of Strife a movement of that kind. | |
| From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 333b23 | |
| A reaction: I take this to be of interest for showing Aristotle's quest for explanations, and his unwillingness to be fobbed off with anything superficial. I take a task of philosophy to be to push explanations further than others wish to go. |
| 460 | If the one Being ever diminishes it would no longer exist, and what could ever increase it? [Empedocles] |
| Full Idea: Besides these elements, nothing else comes into being, nor does anything cease. For if they had been perishing continuously, they would Be no more; and what could increase the Whole? And whence could it have come? | |
| From: Empedocles (fragments/reports [c.453 BCE], B017), quoted by Simplicius - On Aristotle's 'Physics' 158.1- |
| 5090 | Maybe bodies are designed by accident, and the creatures that don't work are destroyed [Empedocles, by Aristotle] |
| Full Idea: Is it just an accident that teeth and other parts of the body seem to have some purpose, and creatures survive because they happen to be put together in a useful way? Everything else has been destroyed, as Empedocles says of his 'cow with human head'. | |
| From: report of Empedocles (fragments/reports [c.453 BCE], 61) by Aristotle - Physics 198b29 | |
| A reaction: Good grief! Has no one ever noticed that Empedocles proposed the theory of evolution? It isn't quite natural selection, because we aren't told what does the 'destroying', but it is a little flash of genius that was quietly forgotten. |
| 461 | God is a pure, solitary, and eternal sphere [Empedocles] |
| Full Idea: God is equal in all directions to himself and altogether eternal, a rounded Sphere enjoying a circular solitude. | |
| From: Empedocles (fragments/reports [c.453 BCE], B028), quoted by John Stobaeus - Anthology 1.15.2 |
| 466 | God is pure mind permeating the universe [Empedocles] |
| Full Idea: God is mind, holy and ineffable, and only mind, which darts through the whole cosmos with its swift thought. | |
| From: Empedocles (fragments/reports [c.453 BCE], B134), quoted by Ammonius - On 'De Interpretatione' 4.5.249.6 |
| 1719 | In Empedocles' theory God is ignorant because, unlike humans, he doesn't know one of the elements (strife) [Aristotle on Empedocles] |
| Full Idea: It is a consequence of Empedocles' view that God is the most unintelligent thing, for he alone is ignorant of one of the elements, namely strife, whereas mortal creatures are familiar with them all. | |
| From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - De Anima 410b08 |
| 1522 | It is wretched not to want to think clearly about the gods [Empedocles] |
| Full Idea: Wretched is he who cares not for clear thinking about the gods. | |
| From: Empedocles (fragments/reports [c.453 BCE], B132), quoted by Clement - Miscellanies 5.140.5.1 |