Some typos

[ionathanch]

@rzach A quick question: Where are the chapter summaries located (referenced to as \OLEndChapterHook in the TeX)? In the summary of chapter 5 of SLC there's a typo in the second sentence of the last paragraph: A ⊧ should be ⊧ A.

EDIT: Whoops never mind! It's already been fixed in the latest PDF, just not in my print copy. For future reference though, it'd be useful to know where those summaries are.

[rzach]

They're in https://github.com/rzach/sets-logic-computation in the include directory

[ionathanch]

Well I've reached the end of IC so that should be all the fixes I have. A few things to note:

• It seems like a big portion of the Lambda Calculus chapter has been rewritten/reorganized since the print version, so I've left most of that alone.
• In second-order-arithmetic/metatheory/second-order-arithmetic.tex, the proof of sol-pa-definable appears to be incomplete: the statement claims that + and × are definable in PA²† as well, but only ≤ is proven. I don't know if there was meant to be a proof, or if it was truncated on purpose for space, or if they're left as exercises.
• The commit with the most substantial changes was 5bdc40451ccbc3667e270751aca0f35b0d589c89, so that should probably be looked at more closely than the others.

@rzach You can review and merge etc. this now. Let me know if you need me to squash the commits or anything (although I think that can be done within GitHub).

[rzach]

Thanks for all your work! I'll have to have a closer look at the second-order logic issues when I'm near my books next, but everything else looks fine.