Combining Texts

All the ideas for 'To be is to be the value of a variable..', 'Counting and the Natural Numbers' and 'Ignorance: a Case for Scepticism'

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17 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...'
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / d. Natural numbers
The essence of natural numbers must reflect all the functions they perform [Sicha]
     Full Idea: What is really essential to being a natural number is what is common to the natural numbers in all the functions they perform.
     From: Jeffrey H. Sicha (Counting and the Natural Numbers [1968], 2)
     A reaction: I could try using natural numbers as insults. 'You despicable seven!' 'How dare you!' I actually agree. The question about functions is always 'what is it about this thing that enables it to perform this function'.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
To know how many, you need a numerical quantifier, as well as equinumerosity [Sicha]
     Full Idea: A knowledge of 'how many' cannot be inferred from the equinumerosity of two collections; a numerical quantifier statement is needed.
     From: Jeffrey H. Sicha (Counting and the Natural Numbers [1968], 3)
Counting puts an initial segment of a serial ordering 1-1 with some other entities [Sicha]
     Full Idea: Counting is the activity of putting an initial segment of a serially ordered string in 1-1 correspondence with some other collection of entities.
     From: Jeffrey H. Sicha (Counting and the Natural Numbers [1968], 2)
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'.
13. Knowledge Criteria / C. External Justification / 6. Contextual Justification / b. Invariantism
The meaning of 'know' does not change from courtroom to living room [Unger]
     Full Idea: There is no reason to suppose that the meaning of 'know' changes from the courtroom to the living room and back again; no more than for supposing that 'vacuum' changes from the laboratory to the cannery.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], 2.1)
     A reaction: I disagree. Lots of words change their meaning (or reference) according to context. Flat, fast, tall, clever. She 'knows a lot' certainly requires a context. The bar of justification goes up and down, and 'knowledge' changes accordingly.
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
No one knows anything, and no one is ever justified or reasonable [Unger]
     Full Idea: I argue for the thesis that no one ever knows about anything, ...and that consequently no one is ever justified or at all reasonable in anything.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], Intro)
     A reaction: The premiss of his book seems to be that knowledge is assumed to require certainty, and is therefore impossible. Unger has helped push us to a more relaxed and fallibilist attitude to knowledge. 'No one is reasonable' is daft!
13. Knowledge Criteria / D. Scepticism / 4. Demon Scepticism
An evil scientist may give you a momentary life, with totally false memories [Unger]
     Full Idea: The evil scientist might not only be deceiving you with his electrodes; maybe he has just created you with your ostensible memory beliefs and experiences, and for good measure he will immediately destroy you, so in the next moment you no longer exist.
     From: Peter Unger (Ignorance: a Case for Scepticism [1975], 1.12)
     A reaction: This is based on Russell's scepticism about memory (Idea 2792). Even this very train of thought may not exist, if the first half of it was implanted, rather than being developed by you. I cannot see how to dispute this possibility.