Tolerance of Ambiguity

"If you think learning is hard, try unlearning."

In his wonderful speech -- You and Your Research -- the great computer scientist Richard Hamming has the following to say on the subject of ambiguity (my emphasis):

There's another trait on the side which I want to talk about; that trait is ambiguity. It took me a while to discover its importance. Most people like to believe something is or is not true. Great scientists tolerate ambiguity very well. They believe the theory enough to go ahead; they doubt it enough to notice the errors and faults so they can step forward and create the new replacement theory. If you believe too much you'll never notice tPublishhe flaws; if you doubt too much you won't get started. It requires a lovely balance. But most great scientists are well aware of why their theories are true and they are also well aware of some slight misfits which don't quite fit and they don't forget it. Darwin writes in his autobiography that he found it necessary to write down every piece of evidence which appeared to contradict his beliefs because otherwise they would disappear from his mind. When you find apparent flaws you've got to be sensitive and keep track of those things, and keep an eye out for how they can be explained or how the theory can be changed to fit them. Those are often the great contributions.

It's almost as if the revolutionary thinkers have a much-more fine-grained mental model of the world, once which allows them to cross the chasm of the unknown that lies between the current understanding to a "replacement theory".