I mentioned a couple of days ago that, in the last four months, the newly available PDFs of my *Intro to Formal Logic *and *Intro to Gödel’s Theorems *have both been downloaded over 3.5K times (and that’s ignoring an initial flurry of downloads of the Gödel book by people who clicked on a probably misleading link posted elsewhere). In the same period — without any advertising at all — the *Teach Yourself Logic Study Guide* has been downloaded 7.5K times. I mention this to explain again why I feel I ought to give the *TYL* project some love and spend some quality time updating the *Guide*: if it is being downloaded that much, with a big surge at the beginning of semesters, it must be being recommended as useful. So I guess I really ought to make sure it is as useful as it can be, and indeed make sure it reflects what I now think about which texts to recommend. The last full version was a pretty rough-and-ready layered accumulation of bits and pieces of various vintages: it is well past time for an end-to-end rewrite. But heavens, it’s necessarily a slow job, as I revisit texts old and new!

Anyway … here now is the latest version of the new-style Guide up to the rewritten Chapter 6. This reworked chapter covers three inter-connected topics: (a) the elementary informal theory of arithmetic computability, (b) an introduction to formal theories of arithmetic and how they represent computable functions, which leads up to (c) Gödel’s epoch-making incompleteness theorems

My reading recommendations for this chapter haven’t changed a lot. But a feature of the revised Guide is that (after the preliminary chapters), each chapter has a section (or two) giving an extended overview of its theme, from five to ten pages long. These overviews are supposed to be elementary indicators of some of the topics covered by the recommended reading. They can certainly be skipped (that’s clearly signalled): the overviews are included just for those who might find this kind of preliminary orientation helpful. It is difficult to know just how to pitch them, and I will no doubt later revisit the set of overviews to make them more uniform in style and level (so comments appreciated!).

I realize now that the *Teach Yourself Logic Study Guide *has been so-called for over eight years. Maybe I shouldn’t change the “brand” name after all ….