But no! cried Wittgenstein. This is the point, there must be the key. You do not half unlock the lock—the door opens either or it does not. And then, Russell, said Wittgenstein with a grin, then you must hope we have not spent our life struggling to open the wrong door!
—from Bruce Duffy’s The World As I Found It, a novel about the lives and interactions of Betrand Russell, G. E. Moore, and Ludwig Wittgenstein. This is probably the only smile from Wittgenstein in the whole book.