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seen Aug 26 at 7:51

Yes.


Mar
25
revised Is the 'variable' in 'let $y=f(x)$' free, bound, or neither?
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Mar
25
revised Is the 'variable' in 'let $y=f(x)$' free, bound, or neither?
added 16 characters in body
Mar
25
revised Is the 'variable' in 'let $y=f(x)$' free, bound, or neither?
added 16 characters in body
Mar
25
revised Is the 'variable' in 'let $y=f(x)$' free, bound, or neither?
added 167 characters in body
Mar
25
answered Is the 'variable' in 'let $y=f(x)$' free, bound, or neither?
Mar
24
accepted Superstructure with sets as atomic/base entities
Mar
24
answered Superstructure with sets as atomic/base entities
Mar
24
comment how to express the set of natural numbers in ZFC
Another definition lets 0 be the empty set and n +1 be the union of n and {n}. Yet another (I think older) option is to define each n as the equivalence class of sets with cardinality n. The idea underlying these definitions is that a natural number is simply a member of the domain of a model of a certain theory. That is, it doesn't matter or make sense to ask what the objects themselves are; only how they relate to each other (i.e., the relations defined on them) is relevant.
Mar
23
comment Infinite Disjunctions and Conjunctions
@Hayden, My reply was longish, so I edited it in above.
Mar
23
revised Infinite Disjunctions and Conjunctions
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Mar
23
answered Infinite Disjunctions and Conjunctions
Mar
23
comment First order logic with N quantifiers - the number of members in the domain matters for validity/consistency in this situation?
It sounds like you might have an odd conception of quantifiers. Could you say what you think quantifiers are, how they work, or what your own reasoning about the answer is?
Mar
22
comment Predicate Logic Problem
Your (b) is right. Why would (a) and (d) be different from (b), aside from the negation? Why do you think they are not also implications? Right now, (a) says that everything is a blue truck that Ross likes, and (d) says that everything is a person, neither of which is what you want to say. You need to put some of these predications in an antecedent (or some equivalent construction). Also, there is a typo in (c) -- you're missing Rachel.
Mar
21
revised Natural and formal languages
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Mar
21
awarded  Commentator
Mar
21
comment Natural and formal languages
@RobertS.Barnes, I don't know if Boolos' book has solutions in it, but Hodges has complete solutions for every problem. The Boolos book is popular enough that you can find material online from courses that use it. For example, I just found this manual (by one of the authors) of hints for odd-#ed problems online: princeton.edu/~jburgess/ManualA.pdf
Mar
20
answered Natural and formal languages
Mar
20
comment How should I understand “$A$ unless $B$”?
@Jack, I think it can mean either of those. I edited in further explanation to my answer. The reason that my answer is so horribly long is to try to convince you that there isn't a single logical translation of "A unless B". You cannot rely on a superficial analysis of the structure. You must also consider the meaning, and you must consider the meaning in context, which includes prior discourse, common knowledge, etc. And even then, you might still be left with ambiguity. That's natural language.
Mar
20
revised How should I understand “$A$ unless $B$”?
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Mar
19
revised Propositional calculus and preferences.
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