Take a moment to think about the context in which your next decision will occur: You did not pick your parents or the time and place of your birth. Y… - Sam Harris

That which is aware of sadness is not sad. That which is aware of fear is not fearful. The moment I am lost in thought, however, I'm as confused as anyone else.

We are conscious of only a tiny fraction of the information that our brains process in each moment.1 Although we continually notice changes in our experience — in thought, mood, perception, behavior, etc. — we are utterly unaware of the neurophysiological events that produce them. In fact, we can be very poor witnesses to experience itself. By merely glancing at your face or listening to your tone of voice, others are often more aware of your state of mind and motivations than you are.

I generally start each day with a cup of coffee or tea — sometimes two. This morning, it was coffee (two). Why not tea? I am in no position to know. I wanted coffee more than I wanted tea today, and I was free to have what I wanted. Did I consciously choose coffee over tea? No. The choice was made for me by events in my brain that I, as the conscious witness of my thoughts and actions, could not inspect or influence. Could I have “changed my mind” and switched to tea before the coffee drinker in me could get his bearings? Yes, but this impulse would also have been the product of unconscious causes. Why didn’t it arise this morning? Why might it arise in the future? I cannot know. The intention to do one thing and not another does not originate in consciousness — rather, it appears in consciousness, as does any thought or impulse that might oppose it.

The physiologist Benjamin Libet famously used EEG to show that activity in the brain’s motor cortex can be detected some 300 milliseconds before a person feels that he has decided to move.2 Another lab extended this work using functional magnetic resonance imaging (fMRI): Subjects were asked to press one of two buttons while watching a “clock” composed of a random sequence of letters appearing on a screen. They reported which letter was visible at the moment they decided to press one button or the other. The experimenters found two brain regions that contained information about which button subjects would press a full 7 to 10 seconds be

You are not in control of your mind — because you, as a conscious agent, are only part of your mind, living at the mercy of other parts.15 You can do what you decide to do — but you cannot decide what you will decide to do. Of course, you can create a framework in which certain decisions are more likely than others — you can, for instance, purge your house of all sweets, making it very unlikely that you will eat dessert later in the evening — but you cannot know why you were able to submit to such a framework today when you weren’t yesterday.
So it’s not that willpower isn’t important or that it is destined to be undermined by biology. Willpower is itself a biological phenomenon. You can change your life, and yourself, through effort and discipline — but you have whatever capacity for effort and discipline you have in this moment, and not a scintilla more (or less). You are either lucky in this department or you aren’t — and you cannot make your own luck.