16 ideas
22764 | Ordinary speech is not exact about what is true; we say we are digging a well before the well exists [Sext.Empiricus] |
Full Idea: We must allow ordinary speech to use inexact terms, as it does not seek after what is really true but what is supposed to be true. We speak of digging a well or weaving a cloak, but there is no well or cloak when they are being dug or woven. | |
From: Sextus Empiricus (Against the Logicians (two books) [c.180], II.129) | |
A reaction: Nice examples. The imprecision is reduced if I say I am creating a well, because that implies something that is not yet complete. If I say I intend to dig a well, is that imprecise because the well does not exist? |
9331 | How do we determine which of the sentences containing a term comprise its definition? [Horwich] |
Full Idea: How are we to determine which of the sentences containing a term comprise its definition? | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §2) | |
A reaction: Nice question. If I say 'philosophy is the love of wisdom' and 'philosophy bores me', why should one be part of its definition and the other not? What if I stipulated that the second one is part of my definition, and the first one isn't? |
22762 | Some properties are inseparable from a thing, such as the length, breadth and depth of a body [Sext.Empiricus] |
Full Idea: Some properties are inseparable from the things to which they belong - as are length, breadth and depth from bodies, for without their presence it is impossible to perceive Body. | |
From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.270) | |
A reaction: For the opposite case he suggests a man running, talking or sleeping. He doesn't mention essential natures, but this is clearly correct. We might say that they are properties which need to be mentioned in a full definition. |
16978 | If conceivability is a priori coherence, that implies possibility [Tahko] |
Full Idea: Maybe conceivability could be understood as a priori coherence, which implies possibility. | |
From: Tuomas E. Tahko (The Epistemology of Essence (draft) [2013], 3.2) | |
A reaction: I'm not quite sure why 'a priori' has to be there. Assessing conceivability just is assessing coherence. That couches it as a rational activity, rather than as a purely imaginary one. Trying to conceive a square circle isn't just daydreaming. |
9333 | A priori belief is not necessarily a priori justification, or a priori knowledge [Horwich] |
Full Idea: It is one thing to believe something a priori and another for this belief to be epistemically justified. The latter is required for a priori knowledge. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §8) | |
A reaction: Personally I would agree with this, because I don't think anything should count as knowledge if it doesn't have supporting reasons, but fans of a priori knowledge presumably think that certain basic facts are just known. They are a priori justified. |
9342 | Understanding needs a priori commitment [Horwich] |
Full Idea: Understanding is itself based on a priori commitment. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §12) | |
A reaction: This sounds plausible, but needs more justification than Horwich offers. This is the sort of New Rationalist idea I associate with Bonjour. The crucial feature of the New lot is, I take it, their fallibilism. All understanding is provisional. |
9332 | Meaning is generated by a priori commitment to truth, not the other way around [Horwich] |
Full Idea: Our a priori commitment to certain sentences is not really explained by our knowledge of a word's meaning. It is the other way around. We accept a priori that the sentences are true, and thereby provide it with meaning. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §8) | |
A reaction: This sounds like a lovely trump card, but how on earth do you decide that a sentence is true if you don't know what it means? Personally I would take it that we are committed to the truth of a proposition, before we have a sentence for it. |
9341 | Meanings and concepts cannot give a priori knowledge, because they may be unacceptable [Horwich] |
Full Idea: A priori knowledge of logic and mathematics cannot derive from meanings or concepts, because someone may possess such concepts, and yet disagree with us about them. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §12) | |
A reaction: A good argument. The thing to focus on is not whether such ideas are a priori, but whether they are knowledge. I think we should employ the word 'intuition' for a priori candidates for knowledge, and demand further justification for actual knowledge. |
9334 | If we stipulate the meaning of 'number' to make Hume's Principle true, we first need Hume's Principle [Horwich] |
Full Idea: If we stipulate the meaning of 'the number of x's' so that it makes Hume's Principle true, we must accept Hume's Principle. But a precondition for this stipulation is that Hume's Principle be accepted a priori. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §9) | |
A reaction: Yet another modern Quinean argument that all attempts at defining things are circular. I am beginning to think that the only a priori knowledge we have is of when a group of ideas is coherent. Calling it 'intuition' might be more accurate. |
9339 | A priori knowledge (e.g. classical logic) may derive from the innate structure of our minds [Horwich] |
Full Idea: One potential source of a priori knowledge is the innate structure of our minds. We might, for example, have an a priori commitment to classical logic. | |
From: Paul Horwich (Stipulation, Meaning and Apriority [2000], §11) | |
A reaction: Horwich points out that to be knowledge it must also say that we ought to believe it. I'm wondering whether if we divided the whole territory of the a priori up into intuitions and then coherent justifications, the whole problem would go away. |
22759 | Fools, infants and madmen may speak truly, but do not know [Sext.Empiricus] |
Full Idea: The fool and the infant and the madman at times say something true, but they do not possess knowledge of the true. | |
From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.042) | |
A reaction: This may be correct of someone who is insane, but seems unfair to the fool and the infant. At what age do children begin to know things? If speech was just random nonsense, an accidental truth seems impossible. |
22760 | Madmen are reliable reporters of what appears to them [Sext.Empiricus] |
Full Idea: The madman is a trustworthy criterion of the appearances which occur in madness. | |
From: Sextus Empiricus (Against the Logicians (two books) [c.180], I.062) | |
A reaction: It is hard to conceive of an genuinely insane person deliberately misreporting their hallucinations. They are, of course, the sole witness. |
16975 | Essences are used to explain natural kinds, modality, and causal powers [Tahko] |
Full Idea: Essences are supposed to do a lot of explanatory work: natural kinds can be identified in terms of their essences, metaphysical modality can be reduced to essence, the causal power of objects can be explained with the help of essence. | |
From: Tuomas E. Tahko (The Epistemology of Essence (draft) [2013], 1) | |
A reaction: Natural kinds and modality are OK with me, but I'm dubious about the third one. If an essence explains something's causal powers, I have no idea what an essence might be. Essence are largely characterised in terms of causal powers. |
22763 | We can only dream of a winged man if we have experienced men and some winged thing [Sext.Empiricus] |
Full Idea: He who in his sleep dreams of a winged man does not dream so without having seen some winged thing and a man. And in general it is impossible to find in conception anything which one does not possess as known by experience. | |
From: Sextus Empiricus (Against the Logicians (two books) [c.180], II.058) | |
A reaction: This precisely David Hume's empiricist account of the formation of concepts. Hume's example is a golden mountain, which he got from Aquinas. How do we dream of faces we have never encountered, or shapes we have never seen? |
16976 | Scientific essentialists tend to characterise essence in terms of modality (not vice versa) [Tahko] |
Full Idea: The conception of essence taken for granted in much of the 'scientific essentialist' literature is that essence can be explained in terms of modality (rather than the other way round). | |
From: Tuomas E. Tahko (The Epistemology of Essence (draft) [2013], 2.1) | |
A reaction: [He cites Ellis and Bird] That is, presumably, that they are inclined to say that the essence of gold is a set of necessary properties. Maybe conceptual necessities dictate the properties of gold, and they in turn dictate metaphysical necessities? |
16977 | If essence is modal and laws are necessary, essentialist knowledge is found by scientists [Tahko] |
Full Idea: If essence is conceived in terms of modality and the laws of nature are metaphysically necessary, it seems that the laws of nature constitute essentialist knowledge, so the discovery of essences is mostly due to scientists. | |
From: Tuomas E. Tahko (The Epistemology of Essence (draft) [2013], 2.1) | |
A reaction: This seems muddled to me. The idea that the laws themselves are essences is way off target. No one thinks all knowledge of necessities is essentialist. Mumford, for example, doesn't even believe in laws. |