Combining Texts

All the ideas for 'On Motion', 'Substance and Essence in Aristotle' and 'To be is to be the value of a variable..'

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18 ideas

4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / a. Sets as existing
The use of plurals doesn't commit us to sets; there do not exist individuals and collections [Boolos]
     Full Idea: We should abandon the idea that the use of plural forms commits us to the existence of sets/classes… Entities are not to be multiplied beyond necessity. There are not two sorts of things in the world, individuals and collections.
     From: George Boolos (To be is to be the value of a variable.. [1984]), quoted by Henry Laycock - Object
     A reaction: The problem of quantifying over sets is notoriously difficult. Try http://plato.stanford.edu/entries/object/index.html.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Does a bowl of Cheerios contain all its sets and subsets? [Boolos]
     Full Idea: Is there, in addition to the 200 Cheerios in a bowl, also a set of them all? And what about the vast number of subsets of Cheerios? It is haywire to think that when you have some Cheerios you are eating a set. What you are doing is: eating the Cheerios.
     From: George Boolos (To be is to be the value of a variable.. [1984], p.72)
     A reaction: In my case Boolos is preaching to the converted. I am particularly bewildered by someone (i.e. Quine) who believes that innumerable sets exist while 'having a taste for desert landscapes' in their ontology.
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Monadic second-order logic might be understood in terms of plural quantifiers [Boolos, by Shapiro]
     Full Idea: Boolos has proposed an alternative understanding of monadic, second-order logic, in terms of plural quantifiers, which many philosophers have found attractive.
     From: report of George Boolos (To be is to be the value of a variable.. [1984]) by Stewart Shapiro - Philosophy of Mathematics 3.5
Boolos showed how plural quantifiers can interpret monadic second-order logic [Boolos, by Linnebo]
     Full Idea: In an indisputable technical result, Boolos showed how plural quantifiers can be used to interpret monadic second-order logic.
     From: report of George Boolos (To be is to be the value of a variable.. [1984], Intro) by Øystein Linnebo - Plural Quantification Exposed Intro
Any sentence of monadic second-order logic can be translated into plural first-order logic [Boolos, by Linnebo]
     Full Idea: Boolos discovered that any sentence of monadic second-order logic can be translated into plural first-order logic.
     From: report of George Boolos (To be is to be the value of a variable.. [1984], §1) by Øystein Linnebo - Plural Quantification Exposed p.74
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is clearly a logical concept, and greatly enhances predicate calculus [Boolos]
     Full Idea: Indispensable to cross-reference, lacking distinctive content, and pervading thought and discourse, 'identity' is without question a logical concept. Adding it to predicate calculus significantly increases the number and variety of inferences possible.
     From: George Boolos (To be is to be the value of a variable.. [1984], p.54)
     A reaction: It is not at all clear to me that identity is a logical concept. Is 'existence' a logical concept? It seems to fit all of Boolos's criteria? I say that all he really means is that it is basic to thought, but I'm not sure it drives the reasoning process.
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Second-order quantifiers are just like plural quantifiers in ordinary language, with no extra ontology [Boolos, by Shapiro]
     Full Idea: Boolos proposes that second-order quantifiers be regarded as 'plural quantifiers' are in ordinary language, and has developed a semantics along those lines. In this way they introduce no new ontology.
     From: report of George Boolos (To be is to be the value of a variable.. [1984]) by Stewart Shapiro - Foundations without Foundationalism 7 n32
     A reaction: This presumably has to treat simple predicates and relations as simply groups of objects, rather than having platonic existence, or something.
5. Theory of Logic / G. Quantification / 6. Plural Quantification
We should understand second-order existential quantifiers as plural quantifiers [Boolos, by Shapiro]
     Full Idea: Standard second-order existential quantifiers pick out a class or a property, but Boolos suggests that they be understood as a plural quantifier, like 'there are objects' or 'there are people'.
     From: report of George Boolos (To be is to be the value of a variable.. [1984]) by Stewart Shapiro - Philosophy of Mathematics 7.4
     A reaction: This idea has potential application to mathematics, and Lewis (1991, 1993) 'invokes it to develop an eliminative structuralism' (Shapiro).
Plural forms have no more ontological commitment than to first-order objects [Boolos]
     Full Idea: Abandon the idea that use of plural forms must always be understood to commit one to the existence of sets of those things to which the corresponding singular forms apply.
     From: George Boolos (To be is to be the value of a variable.. [1984], p.66)
     A reaction: It seems to be an open question whether plural quantification is first- or second-order, but it looks as if it is a rewriting of the first-order.
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
Boolos invented plural quantification [Boolos, by Benardete,JA]
     Full Idea: Boolos virtually patented the new device of plural quantification.
     From: report of George Boolos (To be is to be the value of a variable.. [1984]) by José A. Benardete - Logic and Ontology
     A reaction: This would be 'there are some things such that...'
7. Existence / D. Theories of Reality / 11. Ontological Commitment / b. Commitment of quantifiers
First- and second-order quantifiers are two ways of referring to the same things [Boolos]
     Full Idea: Ontological commitment is carried by first-order quantifiers; a second-order quantifier needn't be taken to be a first-order quantifier in disguise, having special items, collections, as its range. They are two ways of referring to the same things.
     From: George Boolos (To be is to be the value of a variable.. [1984], p.72)
     A reaction: If second-order quantifiers are just a way of referring, then we can see first-order quantifiers that way too, so we could deny 'objects'.
9. Objects / D. Essence of Objects / 2. Types of Essence
Aristotelian and Kripkean essentialism are very different theories [Witt]
     Full Idea: The differences between Aristotelian essentialism and Kripke's essentialism are so fundamental and pervasive that it is a serious distortion of both views to think of essentialism as a single theory.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], Intro)
     A reaction: This seems to me to be very important, because there is a glib assumption that when essentialism is needed for modal logic, that we must immediately have embraced what Aristotle was saying. Aristotle was better than Kripke.
9. Objects / D. Essence of Objects / 4. Essence as Definition
An Aristotelian essence is a nonlinguistic correlate of the definition [Witt]
     Full Idea: An Aristotelian essence is a nonlinguistic correlate of the definition of the entity in question.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], Intro)
     A reaction: This is a simple and necessity corrective to the simplistic idea that Aristotle thought that essences just were definitions. Aristotle believes in real essences, not linguistic essences.
9. Objects / D. Essence of Objects / 6. Essence as Unifier
If unity is a matter of degree, then essence may also be a matter of degree [Witt]
     Full Idea: By holding that the most unified beings have essences in an unqualified sense, while allowing that other beings have them in a qualified sense - we can think of unity as a matter of degree.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], 4.3)
     A reaction: This is Witt's somewhat unorthodox view of how we should read Aristotle. I am sympathetic, if essences are really explanatory. That means they are unstable, and would indeed be likely to come in degrees.
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
Essences mainly explain the existence of unified substance [Witt]
     Full Idea: The central function of essence is to explain the actual existence of a unified substance.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], 5 n1)
     A reaction: She is offering an interpretation of Aristotle. Since existence is an active and not a passive matter, the identity of the entity will include its dispositions etc., I presume.
9. Objects / E. Objects over Time / 12. Origin as Essential
Essential properties of origin are too radically individual for an Aristotelian essence [Witt]
     Full Idea: The radical individuality of essential properties of origin makes them unsuitable for inclusion in an Aristotelian essence.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], 6.2)
     A reaction: Nevertheless, Aristotle believes in individual essences, though these seem to be fixed by definitions, which are composed of combinations of universals. The uniqueness is of the whole definition, not of its parts.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
Reality is directional [Witt]
     Full Idea: Reality is directional.
     From: Charlotte Witt (Substance and Essence in Aristotle [1989], 4.5)
     A reaction: [Plucked from context! She attributes the view to Aristotle] This slogan beautifully summarises the 'scientific essentialist' view of reality, based not on so-called 'laws', but on the active powers of the stuffs of reality.
27. Natural Reality / B. Modern Physics / 1. Relativity / a. Special relativity
Motion is not absolute, but consists in relation [Leibniz]
     Full Idea: In reality motion is not something absolute, but consists in relation.
     From: Gottfried Leibniz (On Motion [1677], A6.4.1968), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 3
     A reaction: It is often thought that motion being relative was invented by Einstein, but Leibniz wholeheartedly embraced 'Galilean relativity', and refused to even consider any absolute concept of motion. Acceleration is a bit trickier than velocity.