Intelligence is an extremely subtle concept. It's a kind of understanding that flourishes if it's combined with a good memory, but exists anyway even in the absence of good memory. It's the ability to draw consequences from causes, to make correct inferences, to foresee what might be the result, to work out logical problems, to be reasonable, rational, to have the ability to understand the solution from perhaps insufficient information. You know when a person is intelligent, but you can be easily fooled if you are not yourself intelligent.
Isaac AsimovGoodbye, Hari, my love. Remember always--all you did for me.” -I did nothing for you.” -You loved me and your love made me--human.
Isaac AsimovIt is precisely because it is fashionable for Americans to know no science, even though they may be well educated otherwise, that they so easily fall prey to nonsense.
Isaac Asimov