Updated to 2.1

This week, more than a decade after the last public update to my book, I updated it to version 2.1. This has some changes from an unreleased draft from 2013, in which I had edited the introduction and added more information about early AHWW. The only changes I made in 2024 were correcting some names, and updating the index, table of contents, and how to cite this document. Otherwise, I’m preserving this as the 2nd edition from more than a decade ago, with outdated research questions and dead links. All of this will be repaired and greatly expanded in the 3rd edition, which is in progress as a collaboration between myself and my partner system, the House of Chimeras.