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Recently retired from Cambridge Philosophy Faculty, interested in logic and philosophy of maths.

I waste time on twitter @PeterSmith (http://twitter.com/PeterSmith/)

For more about me, and links to my blog and website, see http://www.logicmatters.net/about/


2d
comment Introductory example(s) of a functor that is full but not faithful
(1) is particularly nice for giving beginners, thanks!
2d
revised Introductory example(s) of a functor that is full but not faithful
edited body
2d
accepted Introductory example(s) of a functor that is full but not faithful
2d
comment Introductory example(s) of a functor that is full but not faithful
I'm not sure why the downvotes: the deleted plausible-but-wrong answers suggest that the question isn't entirely banal, no?
2d
asked Introductory example(s) of a functor that is full but not faithful
Oct
18
revised Name for introducing negation with quantifiers
added 26 characters in body
Oct
18
answered Name for introducing negation with quantifiers
Oct
18
revised Clarification regarding bound variables and quantifiers
added 227 characters in body
Oct
18
comment Clarification regarding bound variables and quantifiers
In a fixed context, with a standard [single sorted] first-order language, all the variables have the same universe of discourse.
Oct
18
revised Clarification regarding bound variables and quantifiers
added 3 characters in body
Oct
18
answered Clarification regarding bound variables and quantifiers
Oct
17
revised Second order universal quantifier elimination restriction
added 5 characters in body
Oct
13
comment General Strategy for Derivations in Propositional Logic
In just the same sense that Hilbert-Frege style proofs establishing many theorems en route to the target conclusion, a natural deduction derivation establishes many sequents en route to the conclusion. There is no relevant difference.
Oct
9
answered What is the difference between logical and iterative set
Oct
7
revised Text books on computability
added 205 characters in body
Oct
7
answered Text books on computability
Oct
7
revised Is there a Fitch style system that works with some of the modal logics?
added 141 characters in body
Oct
7
answered Is there a Fitch style system that works with some of the modal logics?
Oct
3
revised Finite list of axioms of $\mathsf{ACA}_0$ - reference?
added 3 characters in body
Oct
3
awarded  first-order-logic