The Early Sessions, Book 9

"Concentration in any given area predisposes certain elements within the nervous system toward that particular kind of focus or concentration, as many footfalls hollow out a pathway. Now this is somewhat understood in your scientific circles. What is not understood is that the same sort of conditioning also operates, not only in the reaction to events but in the formation of events. You predispose yourselves toward the construction of events of a particular nature, to which of course you then react. "

Session 472, Page 279