Herbert Stoyan's historical work on early Lisp http://www.mcjones.org/dustydecks/archives/2010/07/29/185/ https://web.archive.org/web/20050617031004/http://www8.infor... is probably worth reading if one is seriously interested. (I haven't read much of it myself yet.) McCarthy praised Stoyan's work as better than his own 1979 HOPL paper ( http://www-formal.stanford.edu/jmc/history/lisp/lisp.html ): "Stoyan's reading of the early LISP documents gives a more accurate picture than my own memories turned out to have given." http://www-formal.stanford.edu/jmc/history/

(As a side-note, I'm pretty sure that the broken, Wayback-beating link to "Lisp references according to Miller" on McCarthy's page is to this http://www.ai.sri.com/~delacaze/alu-site/alu/table/Lisp-Hist... document by Kent Pitman and Brad Miller (see http://www.ai.sri.com/~delacaze/alu-site/alu/table/history.h... ).)