Recording of the singualrity bet Hawking made with Kip Thorn in 1975.
"Whereas Stephen Hawking has such a large investment in general relativity and black holes and desires and insurance policy, and wheras Kip Thorne likes to live dangerously without an insurance policy.
Therefore be it resolved that Stephen Hawking bets one years subscription to PENTHOUSE as against Kip Thorne's wages of a 4-year subscription to PRIVATE EYE, that Cygnus X-1 does not contain a black hole of mass above Chandrasekhar limit."