The body is what the body is fed. By the same token, the mind is what the mind is fed. Mind food, of course, doesn’t come in packages and you can’t but it at the store. Mind food is your environment—all the countless things which influence your conscious and subconscious thought. The kind of mind food we consume determines our habits, attitudes, personality. Each of us inherited a certain capacity to develop. But how much of that capacity we have developed and the way we have developed that capacity depends on the kind of mind food we’ve been fed.
The mind reflects what its environment feeds it just as surely as the body reflects the food you feed it.
~ David J. Schwartz, The Magic of Thinking Big, (1959)