The following article is essentially a review of ideas put forward in a book published nearly a century and a half ago but which deserve to be more widely known. What follows should be read as a supplement to discussion of the subject elsewhere, notably in the detailed appendix to Gary Bates’ book Alien Intrusion: UFOs and the evolution connection.1 A lightly-edited version of the latter is available here: Who were the ‘sons of God’ in Genesis 6? We strongly urge anyone who wishes to comment on the present article to read that latter link first.CMI recognises that evangelical Christians...