> he had an ability to generate, with respect to any given problem, a good many hypotheses, with little initial constraint by previous knowledge as to their plausibility or feasibility;

I think this agrees with something I read years ago: you can tell those who are really creative or not by the way they look at a bike: it they see a bike, they are regular. If they see a lot of components interconnected, then they have more creative ideas because they can see small parts that can be reorganized to creat new things.