17 ideas
| 22462 | We should speak the truth, but also preserve and pursue it [Foot] |
| Full Idea: There belongs to truthfulness not only the avoidance of lying but also that other kind of attachment to truth which has to do with its preservation and pursuit. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.74) | |
| A reaction: This is truth as a value, rather than as a mere phenomenon of accurate thought and speech. The importance of 'preserving' the truth is the less common part of this idea. |
| 10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
| Full Idea: 'Equivocation' is when the terms do not mean the same thing in the premises and in the conclusion. | |
| From: JC Beall / G Restall (Logical Consequence [2005], Intro) |
| 10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall] |
| Full Idea: Logic is purely formal either when it is invariant under permutation of object (Tarski), or when it has totally abstracted away from all contents, or it is the constitutive norms for thought. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) | |
| A reaction: [compressed] The third account sounds rather woolly, and the second one sounds like a tricky operation, but the first one sounds clear and decisive, so I vote for Tarski. |
| 10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
| Full Idea: Technical work on logical consequence has either focused on proofs, where validity is the existence of a proof of the conclusions from the premises, or on models, which focus on the absence of counterexamples. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
| Full Idea: Two different views of logical consequence are necessary truth-preservation (based on modelling possible worlds; favoured by Realists), or truth-preservation based on the meanings of the logical vocabulary (differing in various models; for Anti-Realists). | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) | |
| A reaction: Thus Dummett prefers the second view, because the law of excluded middle is optional. My instincts are with the first one. |
| 10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
| Full Idea: A logical step is a 'material consequence' and not a formal one, if we need the contents as well as the structure or form. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) |
| 10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
| Full Idea: If a conclusion follows from an empty collection of premises, it is true by logic alone, and is a 'logical truth' (sometimes a 'tautology'), or, in the proof-centred approach, 'theorems'. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 4) | |
| A reaction: These truths are written as following from the empty set Φ. They are just implications derived from the axioms and the rules. |
| 10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
| Full Idea: Models are abstract mathematical structures that provide possible interpretations for each of the non-logical primitives in a formal language. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 15938 | Platonists ruin infinity, which is precisely a growing structure which is never completed [Dummett] |
| Full Idea: The platonist destroys the whole essence of infinity, which lies in the conception of a structure which is always in growth, precisely because the process of construction is never completed. | |
| From: Michael Dummett (Elements of Intuitionism [1977], p.57), quoted by Thomas J. McKay - Plural Predication | |
| A reaction: I don't warm to intuitionism, but I warm to this conception of infinity. Completed infinities are convenient reifications for mathematicians. |
| 10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
| Full Idea: There are many proof-systems, the main being Hilbert proofs (with simple rules and complex axioms), or natural deduction systems (with few axioms and many rules, and the rules constitute the meaning of the connectives). | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 15939 | For intuitionists it is constructed proofs (which take time) which make statements true [Dummett] |
| Full Idea: For an intuitionist a mathematical statement is rendered true or false by a proof or disproof, that is, by a construction, and constructions are effected in time. | |
| From: Michael Dummett (Elements of Intuitionism [1977], p.336), quoted by Shaughan Lavine - Understanding the Infinite VI.2 | |
| A reaction: Lavine is quoting this to draw attention to the difficulties of thinking of it as all taking place 'in time', especially when dealing with infinities. |
| 22458 | Consequentialists can hurt the innocent in order to prevent further wickedness [Foot] |
| Full Idea: For consequentialists there will be nothing that it will not be right to do to a perfectly innocent individual, if that is the only way of preventing another agent from doing more things of the same kind. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.61) | |
| A reaction: This is her generalised version that Williams dramatised as Jim and the Indians. Roughly, if you achieve a good outcome, it matters little how it is achieved. Foot sees consequentialism as the main problem with utilitarianism. |
| 22460 | Why might we think that a state of affairs can be morally good or bad? [Foot] |
| Full Idea: We should ask why we think that it makes sense to talk about morally good and bad states of affairs. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.68) | |
| A reaction: This is the key question in her attack on consequentialism. There is nothing 'morally' good about my football team winning a great victory. |
| 22461 | Good outcomes are not external guides to morality, but a part of virtuous actions [Foot] |
| Full Idea: It is not that maximum welfare or 'the best outcome' stands outside morality as it foundation and arbiter, but rather that it appears within morality as the end of one of the virtues. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.73) | |
| A reaction: She cites justice and benevolence as aiming at different (and even conflicting) outcomes. I'm not sure about her distinction between 'outside' and 'within' morality. I suppose a virtuously created end is a moral end, unlike mere good states of affairs. |
| 22464 | The idea of a good state of affairs has no role in the thought of Aristotle, Rawls or Scanlon [Foot] |
| Full Idea: The idea of the goodness of total states of affairs played no part in Aristotle's moral philosophy, and in modern times plays not part either in Rawls's account of justice or in the theories of more thoroughgoing contractualists such as Scanlon. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.76) | |
| A reaction: We can add Kant to that. But if the supremely good state of affairs were permanently achieved, would that make morality irrelevant? A community of the exceptionally virtuous would not need the veil of ignorance, or contracts. |
| 22463 | Morality is seen as tacit legislation by the community [Foot] |
| Full Idea: Morality is thought of as a kind of tacit legislation by the community. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.75) | |
| A reaction: Foot presents this as a utilitarian doctrine, because the tacit legislation is felt to produce the best outcomes. This is Nietzsche's good and evil, beyond which he wished to go (presumably following other values). |
| 22459 | For consequentialism, it is irrational to follow a rule which in this instance ends badly [Foot] |
| Full Idea: It would be irrational to obey even the most useful rule if in a particular instance we clearly see that such obedience will not have the best results. | |
| From: Philippa Foot (Utilitarianism and the Virtues [1985], p.62) | |
| A reaction: This is the simple reason why attempts at rule utilitarianism always lead back to act utilitarianism. Another way of putting it is that a good rule can only be assessed by the outcomes of individual acts that follow it. |