Did you see where he admits he's wrong? "these are logical possibilities". IE, Penrose made a logical argument, and he didn't cover all the cases. Maybe this

Did you see where he admits he's wrong? "these are logical possibilities". IE, Penrose made a logical argument, and he didn't cover all the cases. Maybe this one is clearer: http://www.nytimes.com/books/97/04/27/nnp/17540.html http://www.nytimes.com/books/97/04/27/nnp/17540.html