Combining Texts

All the ideas for 'The Logic of Boundaryless Concepts', 'The Structure of Appearance' and 'Letters to Queen Charlotte'

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13 ideas

4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / a. Sets as existing
Classes are a host of ethereal, platonic, pseudo entities [Goodman]
     Full Idea: I will not willingly use apparatus that peoples the world with a host of ethereal, platonic, pseudo entities.
     From: Nelson Goodman (The Structure of Appearance [1951], II.2), quoted by David Lewis - Parts of Classes 2.1
     A reaction: This represents the big gap that opened up with Goodman's former comrade in arms, Quine. Lewis quotes it in order to ask whether he means ethereal or platonic, as they are very different. I sympathise with Goodman.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Two objects can apparently make up quite distinct arrangements in sets [Goodman, by Burgess/Rosen]
     Full Idea: Goodman argues that the set or class {{a}},{a,b}} is supposed to be distinct from the set or class {{b},{a,b}}, even though both are ultimately constituted from the same a and b.
     From: report of Nelson Goodman (The Structure of Appearance [1951]) by JP Burgess / G Rosen - A Subject with No Object I.A.2.a
     A reaction: I'm with Goodman all the way here, even though it is deeply unfashionable, particularly in the circles I move in. If there are trillion grains of sand on a beach, how many sets are we supposed to be committed to?
4. Formal Logic / G. Formal Mereology / 1. Mereology
The counties of Utah, and the state, and its acres, are in no way different [Goodman]
     Full Idea: A class (counties of Utah) is different neither from the individual (state of Utah) that contains its members, nor from any other class (acres of Utah) whose members exhaust the whole. For nominalists, distinction of entity means distinction of content.
     From: Nelson Goodman (The Structure of Appearance [1951], p.26), quoted by Achille Varzi - Mereology 3.1
     A reaction: This is a nice credo for the nominalist version of mereology. You can still have a mereology that commits you to the wholes as well as the parts. Cf. Lewis in Idea 10660.
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Logic guides thinking, but it isn't a substitute for it [Rumfitt]
     Full Idea: Logic is part of a normative theory of thinking, not a substitute for thinking.
     From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.13)
     A reaction: There is some sort of logicians' dream, going back to Leibniz, of a reasoning engine, which accepts propositions and outputs inferences. I agree with this idea. People who excel at logic are often, it seems to me, modest at philosophy.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
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'.
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
If all and only red things were round things, we would need to specify the 'respect' of the resemblance [Goodman, by Macdonald,C]
     Full Idea: According to Goodman's 'companionship difficulty', resemblance nominalism has a problem if, say, all and only the red things were the round things, because we cannot distinguish the two different respects in which the things resemble one another.
     From: report of Nelson Goodman (The Structure of Appearance [1951]) by Cynthia Macdonald - Varieties of Things Ch.6
     A reaction: Goodman opts for extreme linguististic nominalism in response to this (Idea 7952), whereas Russell opts for a sort of Platonism (4441). The current idea gives Russell a further problem, of needing a universal of the respect of the resemblance.
Without respects of resemblance, we would collect blue book, blue pen, red pen, red clock together [Goodman, by Macdonald,C]
     Full Idea: Goodman's 'imperfect community' problem for Resemblance Nominalism says that without mention of respects in which things resemble, we end up with a heterogeneous collection with nothing wholly in common (blue book, blue pen, red pen, red clock).
     From: report of Nelson Goodman (The Structure of Appearance [1951]) by Cynthia Macdonald - Varieties of Things Ch.6
     A reaction: This suggests Wittgenstein's 'family' resemblance as a way out (Idea 4141), but a blue book and a red clock seem totally unrelated. Nice objection! At this point we start to think that the tropes resemble, rather than the objects.
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
If we apply the same word to different things, it is only because we are willing to do so [Goodman, by Macdonald,C]
     Full Idea: Predicate nominalism is the view that what all things to which the same word applies have in common is simply our willingness to apply the same word to them.
     From: report of Nelson Goodman (The Structure of Appearance [1951], Ch.6) by Cynthia Macdonald - Varieties of Things
     A reaction: This is Goodman's 'extreme nominalist' position. This seems also to be an anti-realist position, as it denies any 'joints' to nature (Idea 7953). It strikes me as daft. WHY are we willing to apply words in certain ways?
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt]
     Full Idea: Vagueness in respect of membership is consistency with determinacy of the set's identity, so long as a set's identity is taken to consist, not in its having such-and-such members, but in its being the extension of a concept.
     From: Ian Rumfitt (The Logic of Boundaryless Concepts [2007], p.5)
     A reaction: I find this view of sets much more appealing than the one that identifies a set with its members. The empty set is less of a problem, as well as non-existents. Logicians prefer the extensional view because it is tidy.
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
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'.
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
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.
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / d. Secondary qualities
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.
12. Knowledge Sources / D. Empiricism / 1. Empiricism
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.