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OpenLogicProject / OpenLogic

An open-source, customizable intermediate logic textbook
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Russel's Paradox typo #339

Open HermesMarc opened 1 year ago

HermesMarc commented 1 year ago

https://github.com/OpenLogicProject/OpenLogic/blob/82a31811a017a839d6415b3f45556eaeeb336cdd/content/computability/computability-theory/russells-paradox.tex#L15-L20

I think this should say "then $S \in S$ if and only if $S \notin S$".

Also: Is the "the set of all sets" trying to refer to S? I would have expected S to be described as "the set of all sets that do not contain themself".

rzach commented 1 year ago

I fixed the typo; the other issue needs more thought. (Briefly: if "the set of all sets" existed, so would S by separation, but this can't easily be explained here. But the whole chapter needs work.)