26 ideas
| 22496 | Wisdom only implies the knowledge achievable in any normal lifetime [Foot] |
| Full Idea: Wisdom implies no more knowledge and understanding than anyone of normal capacity can and should acquire in the course of an ordinary life. | |
| From: Philippa Foot (Natural Goodness [2001], 5) | |
| A reaction: Have philosophers stopped talking about wisdom precisely because you now need three university degrees to be considered even remotely good at phillosophy? Hence wisdom is an inferior attainment, because Foot is right. |
| 13838 | A decent modern definition should always imply a semantics [Hacking] |
| Full Idea: Today we expect that anything worth calling a definition should imply a semantics. | |
| From: Ian Hacking (What is Logic? [1979], §10) | |
| A reaction: He compares this with Gentzen 1935, who was attempting purely syntactic definitions of the logical connectives. |
| 13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
| Full Idea: 'Dilution' (or 'Thinning') provides an essential contrast between deductive and inductive reasoning; for the introduction of new premises may spoil an inductive inference. | |
| From: Ian Hacking (What is Logic? [1979], §06.2) | |
| A reaction: That is, inductive logic (if there is such a thing) is clearly non-monotonic, whereas classical inductive logic is monotonic. |
| 13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
| Full Idea: If A |- B and B |- C, then A |- C. This generalises to: If Γ|-A,Θ and Γ,A |- Θ, then Γ |- Θ. Gentzen called this 'cut'. It is the transitivity of a deduction. | |
| From: Ian Hacking (What is Logic? [1979], §06.3) | |
| A reaction: I read the generalisation as 'If A can be either a premise or a conclusion, you can bypass it'. The first version is just transitivity (which by-passes the middle step). |
| 13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
| Full Idea: Only the cut rule can have a conclusion that is less complex than its premises. Hence when cut is not used, a derivation is quite literally constructive, building up from components. Any theorem obtained by cut can be obtained without it. | |
| From: Ian Hacking (What is Logic? [1979], §08) |
| 13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
| Full Idea: I don't believe English is by nature classical or intuitionistic etc. These are abstractions made by logicians. Logicians attend to numerous different objects that might be served by 'If...then', like material conditional, strict or relevant implication. | |
| From: Ian Hacking (What is Logic? [1979], §15) | |
| A reaction: The idea that they are 'abstractions' is close to my heart. Abstractions from what? Surely 'if...then' has a standard character when employed in normal conversation? |
| 13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
| Full Idea: First-order logic is the strongest complete compact theory with a Löwenheim-Skolem theorem. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
| Full Idea: Henkin proved that there is no first-order treatment of branching quantifiers, which do not seem to involve any idea that is fundamentally different from ordinary quantification. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: See Hacking for an example of branching quantifiers. Hacking is impressed by this as a real limitation of the first-order logic which he generally favours. |
| 13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
| Full Idea: Second-order logic has no chance of a completeness theorem unless one ventures into intensional entities and possible worlds. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
| Full Idea: My doctrine is that the peculiarity of the logical constants resides precisely in that given a certain pure notion of truth and consequence, all the desirable semantic properties of the constants are determined by their syntactic properties. | |
| From: Ian Hacking (What is Logic? [1979], §09) | |
| A reaction: He opposes this to Peacocke 1976, who claims that the logical connectives are essentially semantic in character, concerned with the preservation of truth. |
| 13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
| Full Idea: For some purposes the variables of first-order logic can be regarded as prepositions and place-holders that could in principle be dispensed with, say by a system of arrows indicating what places fall in the scope of which quantifier. | |
| From: Ian Hacking (What is Logic? [1979], §11) | |
| A reaction: I tend to think of variables as either pronouns, or as definite descriptions, or as temporary names, but not as prepositions. Must address this new idea... |
| 13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
| Full Idea: A Löwenheim-Skolem theorem holds for anything which, on my delineation, is a logic. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: I take this to be an unusually conservative view. Shapiro is the chap who can give you an alternative view of these things, or Boolos. |
| 8886 | Being a true justified belief is not a sufficient condition for knowledge [Gettier] |
| Full Idea: The claim that someone knows a proposition if it is true, it is believed, and the person is justified in their belief is false, in that the conditions do not state a sufficient condition for the claim. | |
| From: Edmund L. Gettier (Is Justified True Belief Knowledge? [1963], p.145) | |
| A reaction: This is the beginning of the famous Gettier Problem, which has motivated most epistemology for the last forty years. Gettier implies that justification is necessary, even if it is not sufficient. He gives two counterexamples. |
| 23694 | All criterions of practical rationality derive from goodness of will [Foot] |
| Full Idea: I want to say, baldly, that there is no criterion for practical rationality that is not derived from that of goodness of will. | |
| From: Philippa Foot (Natural Goodness [2001], 1) | |
| A reaction: Where does that put the successful and clever criminal? Presumably they are broadly irrational, but narrowly rational - but that is not very clear distinction. She says Kant's concept of the good will is too pure, and unrelated to human good. |
| 23686 | Moral reason is not just neutral, because morality is part of the standard of rationality [Foot, by Hacker-Wright] |
| Full Idea: In her late period she again reverses her thoughts on moral rationalism; …rather than a neutral rationality which fulfils desires, she argues that morality ought to be thought of as part of the standard of rationality itself. | |
| From: report of Philippa Foot (Natural Goodness [2001]) by John Hacker-Wright - Philippa Foot's Moral Thought Intro | |
| A reaction: This comes much closer to the Greek and Aristotelian concept of logos. They saw morality as inseparable from our judgements about how the world is. All 'sensible' thinking will involve what is good for humanity. |
| 23693 | Practical rationality must weigh both what is morally and what is non-morally required [Foot] |
| Full Idea: Different considerations are on a par, in that judgement about what is required by practical rationality must take account of their interaction: of the weight of the ones we call non-moral as well as those we call moral. | |
| From: Philippa Foot (Natural Goodness [2001], 1) | |
| A reaction: Her final settled view of rationalism in morality, it seems. The point is that moral considerations are not paramount, because she sees possible justifications for ignoring moral rules (like 'don't lie') in certain practical situations. |
| 23687 | Moral virtues arise from human nature, as part of what makes us good human beings [Foot, by Hacker-Wright] |
| Full Idea: In her later work she offers a view of the relationship of morality to human nature, arguing that the moral virtues are part of what makes us good as human beings. | |
| From: report of Philippa Foot (Natural Goodness [2001]) by John Hacker-Wright - Philippa Foot's Moral Thought Intro | |
| A reaction: In this phase she talks explicitly of the Aristotelian idea that successful function is the grounding of what is good for any living being, including humans. |
| 22493 | Sterility is a human defect, but the choice to be childless is not [Foot] |
| Full Idea: Lack of capacity to reproduce is a defect in a human being. But choice of childlessness and even celibacy is not thereby shown to be defective choice, because human good is not the same as plant or animal good. | |
| From: Philippa Foot (Natural Goodness [2001], 3) | |
| A reaction: Is failure to reproduce a defect in an animal? If goodness and virtue derive from function, it is hard to see how deliberate childlessness could be a human good, even if it is not a defect. Choosing to terminate a hereditary defect seems good. |
| 22492 | Virtues are as necessary to humans as stings are to bees [Foot] |
| Full Idea: Virtues play a necessary part in the life of human beings as do stings in the life of a bee. | |
| From: Philippa Foot (Natural Goodness [2001], 2) | |
| A reaction: This presumably rests on the Aristotelian idea that humans are essentially social (as opposed to solitary humans who choose to be social, perhaps in a contractual way, as Plato implies). |
| 22491 | Moral evaluations are not separate from facts, but concern particular facts about functioning [Foot] |
| Full Idea: A moral evaluation does not stand over against the statement of a matter of fact, but rather has to do with facts about a particular subject matter, as do evaluations of such things as sight and hearing in animals. | |
| From: Philippa Foot (Natural Goodness [2001], 1) | |
| A reaction: She avoids the word 'function', and only deals with living creatures, but she uses a 'good knife' as an example, and this Aristotelian view clearly applies to any machine which has a function. |
| 22497 | Deep happiness usually comes from the basic things in life [Foot] |
| Full Idea: Possible objects of deep happiness seem to be things that are basic in human life, such as home, and family, and work, and friendship. | |
| From: Philippa Foot (Natural Goodness [2001], 6) | |
| A reaction: I've not encountered discussion of 'deep' happiness before. I heard of an old man in tears because he had just seen a Purple Emperor butterfly for the first time. She makes it sound very conservative. How about mountaineering achievements? |
| 22498 | Happiness is enjoying the pursuit and attainment of right ends [Foot] |
| Full Idea: In my terminology 'happiness' is understood as the enjoyment of good things, meaning the enjoyment in attaining, and in pursuing, right ends. | |
| From: Philippa Foot (Natural Goodness [2001], 6) | |
| A reaction: A modified version of Aristotle's view, which she contrasts with McDowell's identification of happiness with the life of virtue. They all seem to have an optimistic hope that the pleasure in being a bit wicked is false happiness. |
| 23695 | Good actions can never be justified by the good they brings to their agent [Foot] |
| Full Idea: There is no good case for assessing the goodness of human action by reference only to good that each person brings to himself. | |
| From: Philippa Foot (Natural Goodness [2001], 1) | |
| A reaction: She observes that even non-human animals often act for non-selfish reasons. The significance of this is its rejection of her much earlier view that virtues are justified by the good they bring their possessor. |
| 22499 | We all know that just pretending to be someone's friend is not the good life [Foot] |
| Full Idea: We know perfectly well that it is not true that the best life would consist in successfully pretending friendship: having friends to serve one but without being a real friend oneself. | |
| From: Philippa Foot (Natural Goodness [2001], 7) | |
| A reaction: For some skallywags the achieving of something for nothing seems to be very much the good life, but not many of them want to exploit people who are seen to be their friends. |
| 22495 | Someone is a good person because of their rational will, not their body or memory [Foot] |
| Full Idea: To speak of a good person is to speak of an individual not in respect of his body, or of faculties such as sight and memory, but as concerns his rational will (his 'will as controllable by reason'). | |
| From: Philippa Foot (Natural Goodness [2001], 5) | |
| A reaction: She more or less agrees with Kant that the only truly good moral thing is a good will, though she has plenty of other criticisms of his views. |
| 22502 | Refraining from murder is not made good by authenticity or self-fulfilment [Foot] |
| Full Idea: If a stranger should come on us when we are sleeping he will not think it all right to kill us. …In human life as it is, this kind of action is not made good by authenticity or self-fulfilment in the one who does it. | |
| From: Philippa Foot (Natural Goodness [2001], 7) | |
| A reaction: A rare swipe from Foot at existentialism, which she hardly ever mentions. I find it hard to see these existential virtues as in any way moral. It means nothing to other citizens whether one of their number is 'authentic'. |