24 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. |
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. |
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) |
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. |
5311 | If observation goes up a level, we expect the laws of the lower level to remain in force [Wilson,EO] |
Full Idea: When the observer shifts his attention from one level of organisation to the next, as from physics to chemistry, he expects to find obedience to all the laws of the levels below. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.1) | |
A reaction: This seems to state a necessary condition of reduction, but not a sufficient one. Wilson points out that new phenomena emerge at higher levels. This principle is similar to Hume's argument against miracles. You don't easily overthrow basic laws. |
5312 | A child first sees objects as distinct, and later as members of groups [Wilson,EO] |
Full Idea: From a single-minded effort to move objects a child's activity grows into a detached reflection on the movements themselves. The objects are first perceived as distinct entities, and then as members of groups to be classified. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.3) | |
A reaction: This does not, of course, prove anything about the philosophical problems of universals, but it does seem to pinpoint the stage in human development when 'universals' are perceived. The basis seems to be groups or sets, but how do we spot those? |
5309 | Beliefs are really enabling mechanisms for survival [Wilson,EO] |
Full Idea: Beliefs are really enabling mechanisms for survival. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.1) | |
A reaction: How does he know this proposition which he asserts so confidently? Obvious counterexamples seem to be utterly trivial beliefs, and self-destructive beliefs. What is the evolutionary value of low self-esteem? Still, you see his point. |
2605 | If everything uses mentalese, ALL concepts must be innate! [Putnam] |
Full Idea: Fodor concludes that every predicate that a brain could learn to use must have a translation into the computer language of that brain. So no "new" concepts can be acquired: all concepts are innate! | |
From: Hilary Putnam (What is innate and why [1980], p.407) | |
A reaction: Some misunderstanding, surely? No one could be so daft as to think that everyone has an innate idea of an iPod. More basic innate building blocks for thought are quite plausible. |
2606 | No machine language can express generalisations [Putnam] |
Full Idea: Computers have a built-in language, but not a language that contains quantifiers (that is, the words "all" and "some"). …So generalizations (containing "all") cannot ever be stated in machine language. | |
From: Hilary Putnam (What is innate and why [1980], p.408) | |
A reaction: Computers are too sophisticated to need quantification (which is crude). Computers can work with very precise and complex specifications of the domain of a given variable. |
5310 | Philosophers study the consequences of ethics instead of its origins [Wilson,EO] |
Full Idea: Philosophers examine the precepts of ethical systems with reference to their consequences and not their origins. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.1) | |
A reaction: He is interested in biological origins, but it strikes me that every moral theory has some account of the origins of morality, be it pure reason, or the love of pleasure, or human nature, or eternal ideas, or the will of God, or selfish desires. |
5313 | The rules of human decision-making converge and overlap in a 'human nature' [Wilson,EO] |
Full Idea: The rules followed in human decision-making are tight enough to produce a broad overlap in the decisions taken by all individuals, and hence a convergence powerful enough to be labelled 'human nature'. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.3) | |
A reaction: This is a nice empirical criterion for asserting the existence of human nature, and it seems right to examine decisions, rather than more thoughtless or conformist behaviour. Existentialists dream of new possibilities, but the old ways always seem best… |
5316 | We undermine altruism by rewarding it, but we reward it to encourage it [Wilson,EO] |
Full Idea: By sanctifying altruism in order to reward it we make it less true, but by that means we promote its recurrence in others. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.7) | |
A reaction: So is my preference for not rewarding (or even noticing) altruism an anti-social tendency. The very conspicuous charity of sponsorship seems somehow inferior to the truly anonymous gift. Or super-altruism is very public, to encourage it in others? |
5318 | Pure hard-core altruism based on kin selection is the enemy of civilisation [Wilson,EO] |
Full Idea: Pure hard-core altruism based on kin selection is the enemy of civilisation. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.7) | |
A reaction: By 'hard-core' he means suicidally self-sacrificing, rather than extensive. This seems a good thesis. It strikes me that the development of civil society is often impeded by family loyalty, such as in the case of the Mafia. |
5317 | The actor is most convincing who believes that his performance is real [Wilson,EO] |
Full Idea: The actor is most convincing who believes that his performance is real. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.7) | |
A reaction: This is a key element of social contract theory. It shows why natural selection of truly altruistic traits might be beneficial to individuals, provided they are surrounded by possible recipricators. We trust those who are genuine and sincere. |
5308 | The only human purpose is that created by our genetic history [Wilson,EO] |
Full Idea: No species, ours included, possesses a purpose beyond the imperatives created by its genetic history. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.1) | |
A reaction: This invites the question of what that purpose is perceived to be. Some people feel an imperative to play the piano all day, so presumably genetic history has created that feeling. Presumably we can also choose a purpose, even extinction. |
5314 | Cultural evolution is Lamarckian and fast, biological evolution is Darwinian and slow [Wilson,EO] |
Full Idea: Cultural evolution is Lamarckian and very fast, whereas biological evolution is Darwinian and usually very slow. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.4) | |
A reaction: An intriguing point, given how discredited Lamarckian evolution is. It links with the Dawkins idea of 'memes' - cultural ideas which spread very fast. Is biological evolution suddenly about to become Lamarckian, as culture influences biology? |
5315 | Over 99 percent of human evolution has been in the hunter-gatherer phase [Wilson,EO] |
Full Idea: Selection pressures of hunter-gatherer existence have persisted for over 99 percent of human genetic evolution. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.4) | |
A reaction: This seems a key point to bear in mind when assessing human nature. Hunter-gathering isn't just one tendency in our genetics; it more or less constitutes everything we are. |
5320 | It is estimated that mankind has produced 100,000 religions [Wilson,EO] |
Full Idea: Since the first recorded religion (in Iraq 60,000 years ago) it is estimated that mankind has produced in the order of one hundred thousand religions. | |
From: Edmund O. Wilson (On Human Nature [1978], Ch.8) | |
A reaction: If asked to guess the number, I would probably have said '200'! This staggering figure seems to argue both ways - it suggest a certain arbitrariness in the details of religions, but an extremely intense drive to have some sort of religious belief. |