If you suddenly feel like you’ve had a breakthrough in a field you’re not an expert in, more often than not you haven’t actually understood anything—it’s just the other person being intellectually accommodating.

A beautiful female reporter asked Einstein to explain what the theory of relativity was. He thought for a moment and replied, "When you're with an unattractive girl, an hour feels as long as a day; but with a beauty like you, an hour feels as short as a second." The beautiful reporter was delighted and smiled radiantly.

You don't actually understand the theory of relativity—you just understand the analogy. And that analogy was improvised on the spot by the other person, crafted specifically to cater to you. If you truly want to understand—or to master the theory of relativity yourself—there's no way around those tedious mathematical derivations.

Often, gaining experience and simply understanding something are mutually exclusive.

At all times, the familiar makes money from the unfamiliar—the knowledgeable make money from the ignorant.