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Single Idea 10699

[filed under theme 4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory ]

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.

Clarification

From the context, we can take Cheerios to be a breakfast cereal!

Gist of Idea

Does a bowl of Cheerios contain all its sets and subsets?

Source

George Boolos (To be is to be the value of a variable.. [1984], p.72)

Book Ref

Boolos,George: 'Logic, Logic and Logic' [Harvard 1999], 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.


The 31 ideas from George Boolos

The logic of ZF is classical first-order predicate logic with identity [Boolos]
Mathematics and science do not require very high orders of infinity [Boolos]
The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos]
Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos]
It is lunacy to think we only see ink-marks, and not word-types [Boolos]
I am a fan of abstract objects, and confident of their existence [Boolos]
We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos]
Mathematics isn't surprising, given that we experience many objects as abstract [Boolos]
Infinite natural numbers is as obvious as infinite sentences in English [Boolos]
A few axioms of set theory 'force themselves on us', but most of them don't [Boolos]
An 'abstraction principle' says two things are identical if they are 'equivalent' in some respect [Boolos]
Limitation of Size is weak (Fs only collect is something the same size does) or strong (fewer Fs than objects) [Boolos, by Potter]
Do the Replacement Axioms exceed the iterative conception of sets? [Boolos, by Maddy]
Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley]
Why should compactness be definitive of logic? [Boolos, by Hacking]
A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos]
Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos]
'∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos]
Many concepts can only be expressed by second-order logic [Boolos]
Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos]
Second-order quantifiers are just like plural quantifiers in ordinary language, with no extra ontology [Boolos, by Shapiro]
We should understand second-order existential quantifiers as plural quantifiers [Boolos, by Shapiro]
Boolos invented plural quantification [Boolos, by Benardete,JA]
Monadic second-order logic might be understood in terms of plural quantifiers [Boolos, by Shapiro]
The use of plurals doesn't commit us to sets; there do not exist individuals and collections [Boolos]
Boolos showed how plural quantifiers can interpret monadic second-order logic [Boolos, by Linnebo]
Any sentence of monadic second-order logic can be translated into plural first-order logic [Boolos, by Linnebo]
Identity is clearly a logical concept, and greatly enhances predicate calculus [Boolos]
Plural forms have no more ontological commitment than to first-order objects [Boolos]
Does a bowl of Cheerios contain all its sets and subsets? [Boolos]
First- and second-order quantifiers are two ways of referring to the same things [Boolos]