One curiosity is the original deals with 38 fallacies, while according to the comments, a new version for Christian teaching deals with only 36.
It looks like the 36 lesson title is most likely an earlier edition of the current 38 lesson title. The comments you refer to were from 2008 and the current edition is listed as the "2009 edition" on their product page. Amazon lists the
36 lesson edition as being published in 2003.
Based on
this article from the MIT Tech, it would seem that the book was written by and marketed primarily to Christians but the content is largely free of any doctrinal content (the article does mention one exception).