17 ideas
| 23249 | The early philosophers thought that reason has its own needs and desires [Frede,M] |
| Full Idea: It is part of the notion of reason according to these philosophers [Socrates, Plato, Aristotle, Stoics] that reason has its own needs and desires. | |
| From: Michael Frede (Intro to 'Rationality in Greek Thought' [1996], p.5) | |
| A reaction: This sounds as if reason is treated as a separate person within a person. Anyone solving a logical puzzle feels that reason has its own compulsion. 'Boulesis' is the desire characteristic of reason. |
| 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. |
| 8845 | An experience's having propositional content doesn't make it a belief [Pryor] |
| Full Idea: To say that experiences have propositional content is not to say that experiences are beliefs. | |
| From: James Pryor (There is immediate Justification [2005], §4) | |
| A reaction: This is important for opponents of foundationalism, because they will not allow a raw experience to act as a justification on its own. Even if concepts, or even propositions, are offered by experience, the crucial evaluation must preceded knowledge. |
| 8842 | The best argument for immediate justification is not the Regress Argument, but considering examples [Pryor] |
| Full Idea: The best argument for immediate justification is not the Regress Argument, but from considering examples, such as I have a headache, I am raising my arm, I am imagining my grandmother, or seeing how dominoes could fill a chessboard. | |
| From: James Pryor (There is immediate Justification [2005], §3) | |
| A reaction: Most of his examples depend on the fact that they cannot be challenged by anyone else, because they are within his own mind. The dominoes require complex thought. The first two could be erroneous if he was dreaming. |
| 8843 | Impure coherentists accept that perceptions can justify, unlike pure coherentists [Pryor] |
| Full Idea: Pure coherentists claim that a belief can only be justified by its relations to other beliefs; impure coherentists are willing to give some non-beliefs, such as perceptual experiences, a justifying role. | |
| From: James Pryor (There is immediate Justification [2005], §4) | |
| A reaction: I think I would vote for the pure version. The distinction that is needed, I think, is between justification and evidence. You have to surmise causal links and explanations before you can see an experience as evidence, and then justification. |
| 8844 | Coherentism rests on the claim that justifications must be beliefs, with propositional content [Pryor] |
| Full Idea: The Master Argument for coherentism is the claim that a justifier requires asserted propositional content, and that only beliefs represent propositions assertively. | |
| From: James Pryor (There is immediate Justification [2005], §4) | |
| A reaction: I think this claim (which Pryor attacks) is correct. A key point is that almost any experience can be delusional, and in need of critical evaluation. We would even only accept an experience as being necessarily veridical after critical evaluation. |
| 8846 | Reasons for beliefs can be cited to others, unlike a raw headache experience [Pryor] |
| Full Idea: If you have reasons for your belief, they should be considerations you could in principle cite, or give, to someone who doubted or challenged the belief. You can't give some else a non-propositional state like a headache. | |
| From: James Pryor (There is immediate Justification [2005], §6) | |
| A reaction: On the whole I agree, but if someone asked you to justify your claim that there is a beautiful sunset over the harbour, you could just say 'Look!'. Headaches are too private. The person must still see that the sunset is red, and not the window. |
| 8847 | Beliefs are not chosen, but you can seek ways to influence your belief [Pryor] |
| Full Idea: Ordinarily we make no intentional choices about what to believe, but one can choose to believe something, and then seek ways to get oneself to believe it. | |
| From: James Pryor (There is immediate Justification [2005], §7) | |
| A reaction: Deliberately reading the articles of a philosopher that you seem to agree with would be an example. Presumably the belief that this is a good belief and should be given support is not itself voluntarily chosen. Ultimately we are helpless. See Idea 1854. |