“Natural experiments get the ball rolling. They give us a peek at possible directions. But they only take us so far. After a certain point, a hypothesis starts to materialize, and another kind of test is required. Exploratory experiments are designed to answer fairly open-ended questions: Would I enjoy doing X? Could I be good at doing Y? Would I be able to make a living doing Z? Once a possible self begins to take form, we need to take more active steps to test the possibility more rigorously. Otherwise, we stay in the realm of daydreams.”