Richard Feynman’s father, Melville, a uniform salesman with a keen amateur interest in science, did everything he could to cultivate in his son an inexhaustible passion for knowing how things work at their core, to fan the flames of his desire to know, to provide him with the mental tools that would help him become a great physicist.

 One day, when Richard was still a child, his father came home with blue and white tiles and arranged them in sequences, one blue and one white, or two white and one blue, two blue and one white, trying to teach the boy to recognize visual rhythms, a basic form of mathematics.

They often explored together natural wonders such as barnacle formations on the beach, and they enjoyed poring over entries in the Encyclopedia Britannica on the most diverse subjects.

Once, after drawing Richard’s attention to the fact that a certain bird was going around preening its feathers, Melville asked him why he thought birds behaved that way.

"Well, maybe they mess up their feathers when they fly and then preen them to put them back together," Richard replied.

His father then suggested a simple way to test this hypothesis: if it were correct, you would expect birds that had just landed to preen their feathers much more than birds that had been walking on the ground for a long time.

So, by observing some birds, father and son concluded that there were no obvious differences between birds that had just landed after a flight and birds that had not.

Richard recognized that his hypothesis was probably wrong and asked his father what the correct answer was.

His father then explained that the birds were bothered by lice, which feed on a protein secreted by feathers.

Then there are mites that eat a waxy substance on the lice's legs, and some bacteria that, in turn, grow in the sugar-like material secreted by the mites.

"So," Melville concluded, "wherever there is a source of food, there is some form of life that finds it." As Richard knew even then, his father had given an answer that was probably incorrect in detail (birds preen their feathers to remove parasites and dust, to align them in an optimal position, and to distribute the oil secreted by a gland). However, the answer was correct in principle, and, in any case, his father had stimulated and encouraged Richard's curiosity, suggesting a test to test his proposed explanation.