An insect tries to escape through the windowpane, tries the same again and again, and does not try the next window which is open and through which it came into the room. A man is able, or at least should be able, to act more intelligently. —George Polya, How To Solve It

Intelligence makes humans capable of many impressive feats. Unlike flies and birds, we don't bang up against windows multiple times trying to get out of our houses. We can travel to the moon. We have taken over the planet. Why? Because intelligence enables us to solve problems.

All problems start the same way. They start unsolved. Each fact humans have figured out was initially unfigured out by us. Then we did something, which converted the unknown fact into a known fact, changed the state of a problem from unsolved to solved.

I emphasize the unknown starting state of problems to make a point: problem solving, the basis of human achievement, depends on a process of discovery, discovery of new facts, new possibilities, new methods, and new ways of thought.

Heuristic—the art and science of discovery—has been integral for human progress. The word "heuristic" is related to "Eureka!"