You’ve got to have models in your head. And you’ve got to array your experience—both vicarious and direct—on this latticework of models. You may have noticed students who just try to remember and pound back what is remembered. Well, they fail in school and in life. You’ve got to hang experience on a latticework of models in your mind.

The beauty of topological insulators lies in their robustness; their surface states are protected against disorder and imperfections.

The most valuable resource in fishing is not the fish, but the wisdom to harvest them responsibly.