13 ideas
| 14025 | The weaker version of Truthmaker: 'truth supervenes on being' [Crisp,TM] |
| Full Idea: The weaker version of Truthmaker is that 'truth supervenes on being'. | |
| From: Thomas M. Crisp (Presentism [2003], 3.4) | |
| A reaction: [He cites Lewis 2001 and Bigelow 1988] This still leaves the difficulty of truths about non-existent things, and truths about possibilities (esp. those that are possible, but are never actualised). What being do mathematical truths supervene on? |
| 14023 | The Truthmaker thesis spells trouble for presentists [Crisp,TM] |
| Full Idea: The Truthmaker thesis (that 'for every truth there is a truthmaker, that is, something whose very existence entails the truth' - Fox 1987) spells trouble for the presentist about time. | |
| From: Thomas M. Crisp (Presentism [2003], 3.4) | |
| A reaction: The point is that presentists can no longer express truths about the past (never mind the future), because the truthmakers for them don't exist. This seems to neglect the power of tense - the truth of the claim that 'p was true'. |
| 14024 | Truthmaker has problems with generalisation, non-existence claims, and property instantiations [Crisp,TM] |
| Full Idea: Truthmaker is controversial: what of truths like 'all ravens are black', or 'there are no unicorns'. And 'John is tall' is not made true by John or the property of being tall, but by the fusion of the two, but what could this non-mereological fusion be? | |
| From: Thomas M. Crisp (Presentism [2003], 3.4) | |
| A reaction: A first move is to include modal facts (or possible worlds) among the truthmakers. The unicorns are tricky, and seem to need all of actuality as their truthmaker. I don't see the tallness difficulty. Predication is odd, but so what? |
| 23026 | We know mathematical axioms, such as subtracting equals from equals leaves equals, by a natural light [Leibniz] |
| Full Idea: It is by the natural light that the axioms of mathematics are recognised. If we take away the same quantity from two equal things, …a thing we can easily predict without having experienced it. | |
| From: Gottfried Leibniz (Letters to Queen Charlotte [1702], p.189) | |
| A reaction: He also says two equal weights will keep a balance level. Plato thinks his slave boy understands halving an area by the natural light, but that is just as likely to be experience. It is too easy to attribut thoughts to a 'natural light'. |
| 13189 | A necessary feature (such as air for humans) is not therefore part of the essence [Leibniz] |
| Full Idea: That which is necessary for something does not constitute its essence. Air is necessary for our life, but our life is something other than air. | |
| From: Gottfried Leibniz (Letters to Queen Charlotte [1702], 1702) | |
| A reaction: Bravo. Why can't modern philosophers hang on to this distinction? They seem to think that because they don't believe in traditional essences they can purloin the word for something else. Same with the word 'abstraction'. |
| 14021 | Worm Perdurantism has a fusion of all the parts; Stage Perdurantism has one part at a time [Crisp,TM] |
| Full Idea: Worm-theoretic Perdurantism says spatio-temporal continuants are mereological fusions of instantaneous temporal parts or stages located at different times; Stage-theoretic Perdurantism says they are instantaneous temporal stages of continuants. | |
| From: Thomas M. Crisp (Presentism [2003], 2.1) | |
| A reaction: [Armstrong, Lewis and Quine defend the first; Sider the second] The Stage view seems to be the common sense view. Sider suggests that the earlier stages are counterparts, not the thing as it currently is. |
| 19432 | Intelligible truth is independent of any external things or experiences [Leibniz] |
| Full Idea: Intelligible truth is independent of the truth or of the existence outside us of sensible and material things. ....It is generally true that we only know necessary truths by the natural light [of reason] | |
| From: Gottfried Leibniz (Letters to Queen Charlotte [1702], 1702) | |
| A reaction: A nice quotation summarising a view for which Leibniz is famous - that there is a tight correlation between necessary truths and our a priori knowledge of them. The obvious challenge comes from Kripke's claim that scientists can discover necessities. |
| 19430 | We know objects by perceptions, but their qualities don't reveal what it is we are perceiving [Leibniz] |
| Full Idea: We use the external senses ...to make us know their particular objects ...but they do not make us know what those sensible qualities are ...whether red is small revolving globules causing light, heat a whirling of dust, or sound is waves in air. | |
| From: Gottfried Leibniz (Letters to Queen Charlotte [1702], 1702) | |
| A reaction: These seems to be exactly the concept of secondary qualities which Locke was promoting. They are unreliable information about the objects we perceive. Primary qualities are reliable information. I like that distinction. |
| 19431 | There is nothing in the understanding but experiences, plus the understanding itself, and the understander [Leibniz] |
| Full Idea: It can be said that there is nothing in the understanding which does not come from the senses, except the understanding itself, or that which understands. | |
| From: Gottfried Leibniz (Letters to Queen Charlotte [1702], 1702) | |
| A reaction: Given that Leibniz is labelled as a 'rationalist', this is awfully close to empiricism. Not Locke's 'tabula rasa' perhaps, but Hume's experiences plus associations. Leibniz has a much loftier notion of understanding and reason than Hume does. |
| 19000 | Read 'all ravens are black' as about ravens, not as about an implication [Belnap] |
| Full Idea: 'All ravens are black' might profitably be read as saying not that being a raven 'implies' being black, but rather something more like 'Consider the ravens: each one is black'. | |
| From: Nuel D. Belnap (Conditional Assertion and Restricted Quantification [1970], p.7), quoted by Stephen Yablo - Aboutness 04.5 | |
| A reaction: Belnap is more interested in the logic than in the paradox of confirmation, since he evidently thinks that universal generalisations should not be read as implications. I like Belnap's suggestion. |
| 14020 | 'Eternalism' is the thesis that reality includes past, present and future entities [Crisp,TM] |
| Full Idea: I use the term Eternalism for the thesis that reality includes past, present and future entities. (It is sometimes used for the view that all propositions have their truth-value eternally - it is always true or never true). | |
| From: Thomas M. Crisp (Presentism [2003], Intro n.1) | |
| A reaction: 'Eternalism' strikes me as an excellent word for the former meaning, so I shall promote that, and quietly forget the second one. The idea that the future exists has always stuck in my craw, and the belief that Napoleon still exists strikes me as a weird. |
| 14026 | Presentists can talk of 'times', with no more commitment than modalists have to possible worlds [Crisp,TM] |
| Full Idea: We can talk of 'moments of time' as abstract objects. This will be attractive to the presentist. As possible worlds give an economical theory of modal talk, so 'times' gives us a theory for temporal talk. | |
| From: Thomas M. Crisp (Presentism [2003], 3.4) | |
| A reaction: Thus we can utilise 'times', while having no more commitment to them than to possible worlds. Nice. He cites Prior and Fine 1977 and Chisholm 1979. |
| 14022 | The only three theories are Presentism, Dynamic (A-series) Eternalism and Static (B-series) Eternalism [Crisp,TM] |
| Full Idea: Three theories exhaust the options on time: presentism, dynamic eternalism (eternalism with the tensed dynamic A-series view of time, and the totality of events changing over time), and static eternalism (eternalism with the B-series). | |
| From: Thomas M. Crisp (Presentism [2003], 2.4) | |
| A reaction: I think the idea that reality is Static Eternalism is just a misunderstanding, arising from our imaginative ability to take a lofty objective overview of a very fluid reality. The other two are the serious candidates. Present, or Growing-block. |