He actually first mentioned the idea as early as 2004: http://web.archive.org/web/20040602202609/http://homepages.cwi.nl/~tromp/cl/cl.html http://web.archive.o

He actually first mentioned the idea as early as 2004: http://web.archive.org/web/20040602202609/http://homepages.cwi.nl/~tromp/cl/cl.html http://web.archive.org/web/20040602202609/http://homepages.c...