Penrose: The Answer’s Not 42

In 1998, Stephen Hawking laid 50-50 odds that the holy grail of physics, the elusive “theory of everything,” was less than 20 years away.
Around the same time, Hawking’s renowned peer, collaborator and sometime-disputant, Roger Penrose of Oxford University, set out to write a book detailing just how distant the odds actually are of unifying all the laws of physics.
Wired News: Penrose: The Answer’s Not 42