It is exactly a year ago that the self-published version of An Introduction to Gödel’s Theorems was published as a paperback. It has sold over seven hundred copies in that time, and the monthly trend is slowly upwards. That’s three times as many copies as the CUP paperback was selling. But then, this print-on-demand version is a third of the cost! Even so, the sales figure strikes me as surprisingly high, given that the PDF has also been freely available at the same time as the new paperback. I guess it shows that quite a few people, like me, do prefer to work from a physical book, if one is available at a modest price. As far as downloads go, AWStats currently reports about five hundred a month — though who knows exactly what these (rather volatile) download stats really mean. Still, I count do that as overall a happy success!
Who knows if I will ever get round to a third edition. There’s tidying to be done, and I’d quite like to add a bit more around and about the Second Theorem. It would be fun to catch up with some reading and re-reading and re-thinking. But I don’t cringe when I occasionally have occasion to glance at the book: so I’m not yet feeling an urgent push to getting back to revising it right now.