As Cassius said to Brutus (in Julius Caesar) Men at some time are masters of their fates: The fault, dear Brutus, is not in our stars, But in ourselves, that we are underlings. Might you become master of your fate through choice—no matter what the stars say?
This question weighs on leaders who are supposed to make things happen by recognizing a chance for change, developing a vision of the form that change will take, and then enacting it. This process is at odds with seeing the world as governed by forces beyond your control. Even though you can't expect to always succeed, you must believe you can make a meaningful impact through your choices.
But believing is only the start. You must also cultivate a better understanding of the nature of choice—how it functions, and how it affects your behavior—to make the best of it.