The brain is a deeply constrained thinking machine, full of cognitive tradeoffs and zero-sum constraints. Chess professionals and London cabbies can perform seemingly superhuman mental feats as they chunk their world into memorable patterns. However, those same talents make them bad at seeing beyond their chunks, at making sense of games and places they can’t easily understand. ... So if you’re an expert, be proud: You’ve learned to perceive the world in a useful way. Your training has changed the structure of your brain. But don’t forget to think about your blind spots, about all those new patterns that you must struggle to see.