27 ideas
15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
Full Idea: It is far from clear that a definition of truth can lead to a philosophically satisfactory theory of truth. Tarski's theorem on the undefinability of the truth predicate needs resources beyond those of the language for which it is being defined. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: The idea is that you need a 'metalanguage' for the definition. If I say 'p' is a true sentence in language 'L', I am not making that observation from within language L. The dream is a theory confined to the object language. |
15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
Full Idea: In semantic theories of truth (Tarski or Kripke), a truth predicate is defined for an object-language. This definition is carried out in a metalanguage, which is typically taken to include set theory or another strong theory or expressive language. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: Presumably the metalanguage includes set theory because that connects it with mathematics, and enables it to be formally rigorous. Tarski showed, in his undefinability theorem, that the meta-language must have increased resources. |
15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
Full Idea: If truth is not explanatory, truth axioms should not allow proof of new theorems not involving the truth predicate. It is hence said that axiomatic truth should be 'conservative' - not implying further sentences beyond what the axioms can prove. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: [compressed] |
15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
Full Idea: If truth can be explicitly defined, it can be eliminated, whereas an axiomatized notion of truth may bring all kinds of commitments. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: The general principle that anything which can be defined can be eliminated (in an abstract theory, presumably, not in nature!) raises interesting questions about how many true theories there are which are all equivalent to one another. |
15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach] |
Full Idea: Axiomatic theories of truth can be presented within very weak logical frameworks which require very few resources, and avoid the need for a strong metalanguage and metatheory. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) |
15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
Full Idea: The axiomatic approach does not presuppose that truth can be defined. Instead, a formal language is expanded by a new primitive predicate of truth, and axioms for that predicate are then laid down. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
A reaction: Idea 15647 explains why Halbach thinks the definition route is no good. |
15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
Full Idea: According to many deflationists, truth serves merely the purpose of expressing infinite conjunctions. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
A reaction: That is, it asserts sentences that are too numerous to express individually. It also seems, on a deflationist view, to serve for anaphoric reference to sentences, such as 'what she just said is true'. |
15657 | To prove the consistency of set theory, we must go beyond set theory [Halbach] |
Full Idea: The consistency of set theory cannot be established without assumptions transcending set theory. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 2.1) |
15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
Full Idea: The reduction of 2nd-order theories (of properties or sets) to axiomatic theories of truth may be conceived as a form of reductive nominalism, replacing existence assumptions (for comprehension axioms) by ontologically innocent truth assumptions. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
A reaction: I like this very much, as weeding properties out of logic (without weeding them out of the world). So-called properties in logic are too abundant, so there is a misfit with their role in science. |
15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
Full Idea: Quantification over (certain) properties can be mimicked in a language with a truth predicate by quantifying over formulas. Instead of saying that Tom has the property of being a poor philosopher, we can say 'x is a poor philosopher' is true of Tom. | |
From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
A reaction: I love this, and think it is very important. He talks of 'mimicking' properties, but I see it as philosophers mistakenly attributing properties, when actually what they were doing is asserting truths involving certain predicates. |
8724 | The meaning of 'know' does not change from courtroom to living room [Unger] |
Full Idea: There is no reason to suppose that the meaning of 'know' changes from the courtroom to the living room and back again; no more than for supposing that 'vacuum' changes from the laboratory to the cannery. | |
From: Peter Unger (Ignorance: a Case for Scepticism [1975], 2.1) | |
A reaction: I disagree. Lots of words change their meaning (or reference) according to context. Flat, fast, tall, clever. She 'knows a lot' certainly requires a context. The bar of justification goes up and down, and 'knowledge' changes accordingly. |
8722 | No one knows anything, and no one is ever justified or reasonable [Unger] |
Full Idea: I argue for the thesis that no one ever knows about anything, ...and that consequently no one is ever justified or at all reasonable in anything. | |
From: Peter Unger (Ignorance: a Case for Scepticism [1975], Intro) | |
A reaction: The premiss of his book seems to be that knowledge is assumed to require certainty, and is therefore impossible. Unger has helped push us to a more relaxed and fallibilist attitude to knowledge. 'No one is reasonable' is daft! |
8723 | An evil scientist may give you a momentary life, with totally false memories [Unger] |
Full Idea: The evil scientist might not only be deceiving you with his electrodes; maybe he has just created you with your ostensible memory beliefs and experiences, and for good measure he will immediately destroy you, so in the next moment you no longer exist. | |
From: Peter Unger (Ignorance: a Case for Scepticism [1975], 1.12) | |
A reaction: This is based on Russell's scepticism about memory (Idea 2792). Even this very train of thought may not exist, if the first half of it was implanted, rather than being developed by you. I cannot see how to dispute this possibility. |
6685 | 'Subjectivism' is an extension of relativism from the social group to the individual [Graham] |
Full Idea: What is called 'subjectivism' is really just an extension of relativism from the level of the social group to the level of the individual. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.1) | |
A reaction: Personally I prefer to stick with 'relativism', at any level. 'Relative' is a two-place predicate, so we should always specify what is relative to what, unless it is obvious from context. Morality might be relative to God, for example. |
6699 | The chain of consequences may not be the same as the chain of responsibility [Graham] |
Full Idea: From a utilitarian point of view, the error of Archduke Ferdinand's driver (he turned up a cul-de-sac) was the worst in history, ...but the chain of consequences may not be the same as the chain of responsibility. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.7) | |
A reaction: Can you cause something, and yet not be responsible for it? The driver was presumably fully conscious, rational and deliberate. He must share the responsibility for catastrophe, just as he shares in the causing of all the consequences. |
6698 | Negative consequences are very hard (and possibly impossible) to assess [Graham] |
Full Idea: Negative consequences make the extension of the consequences of our actions indefinite, and this means that it is difficult to assess them; it may make it impossible, since there is now no clear sense to the idea of THE consequences of an action at all. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.7) | |
A reaction: The general slogan of 'Do your best' covers most objections to the calculation of consequences. It is no excuse for stealing a wallet that 'at least I wasn't committing genocide'. How easy were the alternative actions to do? |
6700 | We can't criticise people because of unforeseeable consequences [Graham] |
Full Idea: It is unreasonable to say that people have acted badly because of consequences which were not merely unforeseen but unforeseeable. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.7) | |
A reaction: Interesting, and it sounds right. A key question in moral philosophy is how much effort people should make to assess the consequences of their actions. We must surely absolve them of the truly 'unforeseeable' consequence. |
6704 | Egoism submits to desires, but cannot help form them [Graham] |
Full Idea: Egoism is inadequate as a guide to good living. Though it tells us what to do, given pre-existent desires, it cannot help us critically form those desires. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.9) | |
A reaction: A crucial point in morality. It also applies to utilitarianism (should I change my capacity for pleasure?), and virtue theory (how should I genetically engineer 'human nature'?). I think these problems push us towards Platonism. See Idea 4840. |
6701 | Rescue operations need spontaneous benevolence, not careful thought [Graham] |
Full Idea: If more lives are to be saved in natural disasters, what is needed is spontaneity on the part of the rescuers, a willingness not to stop and think but to act spontaneously. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.7) | |
A reaction: This seems right, but must obviously be applied with caution, as when people are drowned attempting hopeless rescues. The most valuable person in an earthquake may be the thinker, not the digger. |
6693 | 'What if everybody did that?' rather misses the point as an objection to cheating [Graham] |
Full Idea: I can object to your walking on the grass by asking 'What if everybody did that?', but the advantages of cheating depend upon the fact that most people don't cheat, so justifying my own cheating must involve special pleading. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.6) | |
A reaction: It is, of course, reasonable to ask 'What if everybody cheated?', but it is also reasonable to reply that 'the whole point of cheating is that it exploits the honesty of others'. This shows that Kant cannot simply demolish the 'free rider'. |
6691 | It is more plausible to say people can choose between values, than that they can create them [Graham] |
Full Idea: To say that individuals are free to choose their own values is more naturally interpreted as meaning that they are free to choose between pre-existent values. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.5) | |
A reaction: Existentialism seems absurdly individualistic in its morality. Nietzsche was the best existentialist, who saw that most people have to be sheep. Strong personalities can promote or demote the old values on the great scale of what is good. |
6688 | Life is only absurd if you expected an explanation and none turns up [Graham] |
Full Idea: If 'life is absurd' just means 'there is no logical explanation for human existence', we have no reason for anguish, unless we think there should be such an explanation. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.5) | |
A reaction: This is aimed at Kierkegaard and Camus. 'Absurd' certainly seems to be a relative notion, and we have nothing to compare life with. However, life does strike us as a bit odd sometimes, don't you think? |
6705 | Existentialism may transcend our nature, unlike eudaimonism [Graham] |
Full Idea: It is the freedom to transcend our nature which eudaimonism seems to ignore and existentialism brings to the fore. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.9) | |
A reaction: It is wildly exciting to 'transcend our nature', and very dreary to polish up the nature which is given to us. In this I am a bit conservative. We should not go against the grain, but we shouldn't assume current living is the correct line of the grain. |
6690 | A standard problem for existentialism is the 'sincere Nazi' [Graham] |
Full Idea: A standard problem for existentialism is the 'sincere Nazi'; there were undoubtedly some true believers, who saw in Nazism a creed that they wanted to believe, and who freely chose to endorse it. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.5) | |
A reaction: The failing of Nazis was that they were not good citizens. They might have been good members of a faction, but they were (in my opinion) poor citizens of Germany, and (obviously) appalling citizens of Europe. The objection to existentialism is good. |
6689 | The key to existentialism: the way you make choices is more important than what you choose [Graham] |
Full Idea: The chief implication of existentialism is this: what you choose to do, how you choose to spend your life, is not as important as the way you choose it. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.5) | |
A reaction: While existentialists place emphasis on some notion of 'pure' choice, this is very close to the virtue theory idea that in a dilemma there may be several different choices which could all be rightly made by virtuous people. Integrity is a central virtue. |
6706 | The great religions are much more concerned with the religious life than with ethics [Graham] |
Full Idea: The fact is that the great religions of the world are not principally concerned with ethics at all, but with the religious life for its own sake. ..The Sermon on the Mount, for example, is mainly concerned with how to pray and worship. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.9) | |
A reaction: This seems to me a highly significant point, given that most people nowadays seem to endorse religion precisely because they wish to endorse morality, and think religion is its essential underpinning. See Idea 336 for the core problem ('Euthyphro'). |
6709 | Western religion saves us from death; Eastern religion saves us from immortality [Graham] |
Full Idea: For Western minds, religion entails the belief and hope that we will be saved from death and live forever, but the belief of Eastern religions is that we do live forever, and it is from this dreadful fate that we must look to spirituality to save us. | |
From: Gordon Graham (Eight Theories of Ethics [2004], Ch.9) | |
A reaction: Nice. I have certainly come to prefer the Eastern view, simply on the grounds that human beings have a limited capacity. I quite fancy three hundred years of healthy life, but after that I am sure that any potential I have will be used up. |