27 ideas
| 1403 | A rational donkey would starve to death between two totally identical piles of hay [Buridan, by PG] |
| Full Idea: A rational donkey faced with two totally identical piles of hay would be unable to decide which one to eat first, and would therefore starve to death | |
| From: report of Jean Buridan (talk [1338]) by PG - Db (ideas) | |
| A reaction: also De Caelo 295b32 (Idea 19740). |
| 16678 | Without magnitude a thing would retain its parts, but they would have no location [Buridan] |
| Full Idea: If magnitude were removed from matter by divine power, it would still have parts distinct from one another, but they would not be positioned either outside one another or inside one another, because position would be removed. | |
| From: Jean Buridan (Questions on Aristotle's Physics [1346], I.8 f. 11va), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 14.4 | |
| A reaction: This shows why Quantity is such an important category for scholastic philosopher. |
| 14637 | Only individuals have essences, so numbers (as a higher type based on classes) lack them [McMichael] |
| Full Idea: Essentialism is not verified by the observation that numbers have interesting essential properties, since they are properties of classes and so are entities of a higher logical type than individuals. | |
| From: Alan McMichael (The Epistemology of Essentialist Claims [1986], Intro) | |
| A reaction: This relies on a particular view of number (which might be challenged), but is interesting when it comes to abstract entities having essences. Only ur-elements in set theory could have essences, it seems. Why? Rising in type destroys essence? |
| 14636 | Essences are the interesting necessary properties resulting from a thing's own peculiar nature [McMichael] |
| Full Idea: Essentialism says some individuals have certain 'interesting' necessary properties. If it exists, it has that property. The properties are 'interesting' as had in virtue of their own peculiar natures, rather than as general necessary truths. | |
| From: Alan McMichael (The Epistemology of Essentialist Claims [1986], Intro) | |
| A reaction: [compressed] This is a modern commentator caught between two views. The idea that essence is the non-trivial-necessary properties is standard, but adding their 'peculiar natures' connects him to Aristotle, and Kit Fine's later papers. Good! |
| 14640 | Maybe essential properties have to be intrinsic, as well as necessary? [McMichael] |
| Full Idea: There is a tendency to think of essential properties as having some characteristic in addition to their necessity, such as intrinsicality. | |
| From: Alan McMichael (The Epistemology of Essentialist Claims [1986], VIII) | |
| A reaction: Personally I am inclined to take this view of all properties, and not just the 'essential' ones. General necessities, relations, categorisations, disjunctions etc. should not be called 'properties', even if they are 'predicates'. Huge confusion results. |
| 14638 | Essentialism is false, because it implies the existence of necessary singular propositions [McMichael] |
| Full Idea: Essentialism entails the existence of necessary singular propositions that are not instances of necessary generalizations. Therefore, since there are no such propositions, essentialism is false. | |
| From: Alan McMichael (The Epistemology of Essentialist Claims [1986], I) | |
| A reaction: This summarises the attack which McMichael wishes to deal with. I am wickedly tempted to say that essences actually have a contingent existence (or a merely hypothetical dependent necessity), and this objection might be grist for my mill. |
| 16793 | A thing is (less properly) the same over time if each part is succeeded by another [Buridan] |
| Full Idea: Less properly, one thing is said to be numerically the same as another according to the continuity of distinct parts, one in succession after another. In this way the Seine is said to be the same river after a thousand years. | |
| From: Jean Buridan (Questions on Aristotle's Physics [1346], I.10, f. 13vb), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 29.3 | |
| A reaction: This is a rather good solution to the difficulty of the looser non-transitive notion of a thing being 'the same'. The Ship of Theseus endures (in the simple case) as long as you remember to replace each departing plank. Must some parts be originals? |
| 16726 | Why can't we deduce secondary qualities from primary ones, if they cause them? [Buridan] |
| Full Idea: The entire difficulty in this question is why through a knowledge of the primary tangible qualities we cannot come to a knowledge of flavors or odors, since these are their causes, since we often go from knowledge of causes to knowing their effects. | |
| From: Jean Buridan (Questions on Aristotle's Posterior Analytics [1344], I.28c), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 22.2 | |
| A reaction: He is commenting on Idea 16725. Still a nice puzzle in the philosophy of mind. Will neuroscientists ever be able to infer to actual character of some quale, just from the structures of the neurons? |
| 16577 | Induction is not demonstration, because not all of the instances can be observed [Buridan] |
| Full Idea: Inductions are not demonstrations, because they do not conclude on account of their form, since it is not possible to make an induction from all cases. | |
| From: Jean Buridan (Questions on Aristotle's Physics [1346], I.15 f. 18vb), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 02.3 | |
| A reaction: Thus showing that demonstration really is meant to be as conclusive as a mathematical proof, and that Aristotle seems to think such a thing is possible in physical science. |
| 16576 | Science is based on induction, for general truths about fire, rhubarb and magnets [Buridan] |
| Full Idea: Induction should be regarded as a principle of natural science. For otherwise you could not prove that every fire is hot, that all rhubarb is purgative of bile, that every magnet attracts iron. | |
| From: Jean Buridan (Questions on Aristotle's Physics [1346], I.15 f. 18vb), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 02.3 | |
| A reaction: He is basing this on Aristotle, and refers to 'Physics' 190a33-b11. |
| 20289 | Ethics is universalisable - it must involve an impartial and universal view of things [Singer] |
| Full Idea: A distinguishng feature of ethics is that ethical judgements are universalisable. Ethics requires us to go beyond our own personal point of view to a standpoint like that of the impartial spectator who takes a universal point of view. | |
| From: Peter Singer (Practical Ethics [1979], 10) | |
| A reaction: I'm thinking that ethical agents are more 'situated' than that. Suppose a finance minister stole billions in tax and gave it to a poor country. Good from the universal angle, perhaps, but a shocking betrayal of his own community. |
| 20286 | Following an inner voice for morality is irresponsible in a rational agent [Singer] |
| Full Idea: When following conscience means doing as one's 'internal voice' prompts one to do, to follow one's conscience it so abdicate one's responsibility as a rational agent. | |
| From: Peter Singer (Practical Ethics [1979], 09) | |
| A reaction: Seems dead right. An inner voice is far more likely to be your culture and upbringing than to be an absolute moral truth. It may not be entirely wrong, though, to behave as your culture requires. |
| 20282 | The sanctity of a human life depends either on being of our species, or on being a person [Singer] |
| Full Idea: The doctrine of the sanctity of human life has two separate claims, one that there is a special value in the life of a member of our species, and the other that there is a special value in the life of a person. | |
| From: Peter Singer (Practical Ethics [1979], 04) |
| 20278 | 'Marginal utility' says something is more useful if it is in short supply [Singer] |
| Full Idea: The economic principle of marginal utility states that for a given individual a set amount of something is more useful when the individual has little of it than when he has a lot. | |
| From: Peter Singer (Practical Ethics [1979], 02) | |
| A reaction: But individuals may very a lot on this one. 'He can't get enough of X'. I may be desperate to buy 10,000 books, but you may consider such a need ridiculous, so who decides? |
| 20281 | Why should I do anything for posterity? What has posterity ever done for me? [Singer] |
| Full Idea: Most striking is the impact of the contract model on our attitude to future generations. 'Why should I do anything for posterity? What has posterity ever done for me?' would be the view we ought to take. | |
| From: Peter Singer (Practical Ethics [1979], 03) | |
| A reaction: I should bury my mobile phone for future archaeologists, because it will be more valuable then than it is now. Singer cites the disposal of nuclear waste as an instance. |
| 20276 | Conflict of rules might be avoided by greater complexity, or by a hierarchy of rules [Singer] |
| Full Idea: Those who think ethics is a system of rules can rescue their position by finding more complicated and more specific rules which do not conflict, or by ranking the rules in some hierarchical structure to resolve conflicts. | |
| From: Peter Singer (Practical Ethics [1979], 01) | |
| A reaction: The problem is that clear-cut rules seem to produce conflicts. I would have thought that more specific rules would increase that problem. Safety is in generality. |
| 20290 | Psychopaths may just be bored, because they cannot participate in normal emotional life [Singer] |
| Full Idea: Maybe psychopaths are bored because their emotional poverty means that they cannot take interest in, or gain satisfaction from, what for others are the most important things in life: love, family, success in business or professional life, etc. | |
| From: Peter Singer (Practical Ethics [1979], 10) | |
| A reaction: [he cites Hervey Cleckley for this] Maybe boredom is a symptom of some human inadequacy, but it might sometimes be a mark of superiority. It drives people to both creation and destruction. Quite a good account of criminal behaviour. |
| 20288 | You can't condemn violent revolution without assessing the evils it prevents [Singer] |
| Full Idea: It would be one-sided to say that violent revolution is always absolutely wrong, without taking account of the evils that the revolutionaries are trying to stop. | |
| From: Peter Singer (Practical Ethics [1979], 09) | |
| A reaction: This seems like common sense, but there are plenty of right-wing authoritarians who would claim that stable authority has priority over all social wrongs. I think that view is mistaken. But the problem is, how to know the future? |
| 21997 | In Marxism the state will be superseded [Singer] |
| Full Idea: It is a famous Marxist doctrine that the state will be superseded. | |
| From: Peter Singer (Marx [1980], 9) | |
| A reaction: Why is that final state communism rather than anarchism? |
| 20287 | If 49% of the population can be wrong, so can 51% [Singer] |
| Full Idea: The case for majority rule should not be overstated. No sensible democrat would claim that the majority is always right. If 49% of the population can be wrong, so can 51%. | |
| From: Peter Singer (Practical Ethics [1979], 09) | |
| A reaction: Well said! We can't possibly put a figure on when the majority become right. In the recent Brexit referendum hardly anyone seemed to understand the issues very well, so none of us have a clue about who was right. |
| 21993 | Materialist history says we are subject to incomprehensible forces [Singer] |
| Full Idea: The materialist conception of history tells us that human beings are totally subject to forces they do not understand and control. | |
| From: Peter Singer (Marx [1980], 6) | |
| A reaction: How does Marx know the forces? An exceptionally influential idea, because it is a modern commonplace that we have very little control over our own lives (apart from right wingers asserting that 'you can have anything if you really really want it'). |
| 20277 | Equality of interests is a minimal principle, not implying equal treatment [Singer] |
| Full Idea: Equal consideration of interests is a minimal principle of equality in the sense that it does not dictate equal treatment. | |
| From: Peter Singer (Practical Ethics [1979], 02) | |
| A reaction: Do those convicted of serious crime retain equal interests? Should a huge group of people sacrifice all of their interests, because of the powerful interests of one person? |
| 20279 | Equality of opportunity unfairly rewards those lucky enough to have great ability [Singer] |
| Full Idea: Equality of opportunity is not an attractive ideal. It rewards the lucky, who inherit those abilities that allow them to pursue interesting and lucrative careers. | |
| From: Peter Singer (Practical Ethics [1979], 02) | |
| A reaction: He makes it sound like cheating. Singer has a highly individualistic view, but society as a whole needs the development of talent, wherever it can be found. |
| 20285 | If a right entails having the relevant desire, many creatures might have no right to life [Singer] |
| Full Idea: If to have a right one must have the ability to desire that to which one has a right, then to have a right to life one must be able to desire one's own continued existence. | |
| From: Peter Singer (Practical Ethics [1979], 07) | |
| A reaction: The unborn, small infants, and persons in comas may well lack the relevant desire (at least consciously - arguably even a plant has a non-conscious 'desire' or drive for life). The idea that a right entails a conscious desire seems daft. |
| 20284 | Why should a potential person have the rights of an actual person? [Singer] |
| Full Idea: A prince may be a potential king, but he does not have the rights of a king. Why should a potential person have the rights of a person? | |
| From: Peter Singer (Practical Ethics [1979], 06) | |
| A reaction: But the prince is probably accorded special rights, merely on the grounds that he is the potential king. An unborn potential king is always considered as special. |
| 20283 | Killing a chimp is worse than killing a human too defective to be a person [Singer] |
| Full Idea: It seems that killing a chimpanzee is worse than the killing of a gravely defective human who is not a person. ...[p.103] the effects on relatives of the defective human will sometimes constitute additional indirect reasons against killing the human. | |
| From: Peter Singer (Practical Ethics [1979], 05) | |
| A reaction: Singer's most notorious idea. Perhaps we should all carry cards (perhaps combined with donor cards) saying how many people will care if we die. |
| 14639 | Individuals enter into laws only through their general qualities and relations [McMichael] |
| Full Idea: Individuals appear to enter into laws only through their general qualities and relations. | |
| From: Alan McMichael (The Epistemology of Essentialist Claims [1986], VIII) | |
| A reaction: This is a very significant chicken-or-egg issue. The remark seems to offer the vision of pre-existing general laws, which individuals then join (like joining a club). But surely the laws are derived from the individuals? Where else could they come from? |