15 ideas
| 13010 | In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine] |
| Full Idea: Quine ends up with the logic that is maximally justified by experience, ...but a large number of the core principles of logic will have to be used to select the logic that is maximally justified by experience. | |
| From: comment on Willard Quine (Carnap and Logical Truth [1954]) by Paul Boghossian - Knowledge of Logic p.233 | |
| A reaction: In order to grasp some core principles of logic, you will probably need a certain amount of experience. I take logic to be an abstracted feature of reality (unless it is extended by pure fictions). Some basic logic may be hard wired in us. |
| 9002 | Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine] |
| Full Idea: Elementary logic, as commonly systematized nowadays, comprises truth-function theory (involving 'or', 'and', 'not' etc.), quantifiers (and their variables), and identity theory ('='). In addition, set theory requires classes among values of variables. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: Quine is famous for trying to squeeze properties out of the picture, which would then block higher-order logics (which quantify over properties). Quine's list gives a nice programme for a student of the philosophy of logic to understand. |
| 13681 | Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider] |
| Full Idea: Quine's view of logical consequence is that it is when there is no way of uniformly substituting nonlogical expressions in the premises and consequences so that the premises all remain true but the consequence now becomes false. | |
| From: report of Willard Quine (Carnap and Logical Truth [1954], p.103) by Theodore Sider - Logic for Philosophy 1.5 | |
| A reaction: One might just say that the consequence holds if you insert consistent variables for the nonlogical terms, which looks like Aristotle's view of the matter. |
| 13829 | If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine] |
| Full Idea: Quine said a logical truth is a truth in which only logical constants occur essentially, ...but then a fruitful definition of 'logical constant' is called for. | |
| From: comment on Willard Quine (Carnap and Logical Truth [1954]) by Ian Hacking - What is Logic? §02 |
| 9003 | Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine] |
| Full Idea: Unlike elementary logic, the truths of set theory are not obvious. Set theory was straining at the leash of intuition ever since Cantor discovered higher infinites; and with the added impetus of the paradoxes of set theory the leash snapped. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: This problem seems to have forced Quine into platonism about sets, because he felt they were essential for mathematics and science, but couldn't be constructed with precision. So they must be real, but we don't quite understand them. |
| 9004 | If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine] |
| Full Idea: We might say that set theory is not really logic, but a branch of mathematics. This would deprive 'includes' of the status of a logical word. Frege's derivation of arithmetic would then cease to count as a derivation from logic: for he used set theory. | |
| From: Willard Quine (Carnap and Logical Truth [1954], II) | |
| A reaction: Quine has been making the point that higher infinities and the paradoxes undermine the status of set theory as logic, but he decides to continue thinking of set theory as logic. Critics of logicism frequently ask whether the reduction is to logic. |
| 9006 | Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine] |
| Full Idea: One's hypothesis as to there being universals is at bottom just as arbitrary or pragmatic a matter as one's adoption of a new brand of set theory or even a new system of bookkeeping. | |
| From: Willard Quine (Carnap and Logical Truth [1954], x) | |
| A reaction: This spells out clearly the strongly pragmatist vein in Quine's thinking. |
| 9001 | Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine] |
| Full Idea: When Kant's arithmetical examples of a priori synthetic judgements were sweepingly disqualified by Frege's reduction of arithmetic to logic, attention moved to the less tendentious and logically prior question 'How is logical certainty possible?' | |
| From: Willard Quine (Carnap and Logical Truth [1954], I) | |
| A reaction: A nice summary of the story so far, from someone who should know. This still leaves the question open of whether any synthetic truths can be derived from the logical certainties which are available. |
| 9005 | Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine] |
| Full Idea: In trying to make sense of the role of convention in a priori knowledge, the very distinction between a priori and empirical begins to waver and dissolve. | |
| From: Willard Quine (Carnap and Logical Truth [1954], VI) | |
| A reaction: This is the next stage in the argument after Wittgenstein presents the apriori as nothing more than what arises from truth tables. The rationalists react by taking us back to the original 'natural light of reason' view. Then we go round again... |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
| Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice. | |
| From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where? |
| 22594 | In 1794 France all individual and legal rights were suppressed by the general will [Dunt] |
| Full Idea: In the French Revolution the general will replaced democracy, the separation of powers, the rule of law, and individual rights. | |
| From: Ian Dunt (How to be a Liberal [2020], 03) | |
| A reaction: I had some sympathy with the idea of the general will, but Dunt has persuaded me otherwise. It is the embodiment of the democratic problem of the tyranny of the majority. |
| 22602 | Over several centuries a set of eight main liberal values was established [Dunt] |
| Full Idea: Over the centuries liberal values were established: freedom of the individual, reason, consent in government, individual rights, the separation of powers, protection of minorities, autonomy, and moderation. | |
| From: Ian Dunt (How to be a Liberal [2020], 13) | |
| A reaction: What's not to like? 'Moderation' might be a sticking point, for anyone who thinks that very large social changes are needed. |
| 22596 | No government, or the whole nation, can control an individual beyond legitimate scope [Dunt] |
| Full Idea: When a government of any sort puts a threatening hand on that part of individual life beyond its proper scope, …even if it were the whole nation, except for the man it is harassing, it would be no more legitimate for that. | |
| From: Ian Dunt (How to be a Liberal [2020]), quoted by Ian Dunt - How to be a Liberal 4 | |
| A reaction: The obvious question is what counts as 'proper scope' - and who gets to define it? If the individual can define that, then criminals can appeal to this principle. The state must be persuaded of it, then asked to stick to it during conflicts. |
| 22603 | Laissez-faire liberalism failed to give people the protections and freedoms needed for a good life [Dunt] |
| Full Idea: Laissez-faire liberalism failed, because it did not offer people protections and real freedom - against discrimination, insecure work, educational disadvantage, lack of social respect, absence of representation. It was cold, distant, and ineffective. | |
| From: Ian Dunt (How to be a Liberal [2020], 13) | |
| A reaction: A very nice summary, which I take to be correct. |
| 22592 | Nationalism pretends that we can only have a single identity [Dunt] |
| Full Idea: Nationalism pretends that there is only one identity, that we cannot be more than one thing at once. | |
| From: Ian Dunt (How to be a Liberal [2020], Today) | |
| A reaction: Dunt is a defender of liberalism, which assumes a wide degree of pluralism. Could I be a British citizen, but love France more than Britain? I don’t see why not, but it is not an ideal situation. |