When we're in a human body, we don't care about universal collapse - instead, we care only about a meeting of the eyes, a glimpse of bare flesh, the caressing tones of a loved voice, joy, love, light, the orientation of a house plant, the shade of a paint stroke, the arrangement of hair.

The more familiar the world becomes, the less information your brain writes down, and the more quickly time seems to pass.

The left hemisphere acts as an "interpreter," watching the actions and behaviors of the body and assigning a coherent narrative to these events. And the left hemisphere works this way even in normal, intact brains. Hidden programs drive actions, and the left hemisphere makes justifications. This idea of retrospective storytelling suggests that we come to know our own attitudes and emotions, at least partially, by inferring them from observations of our own behavior.

The deep secret of the brain is that not only the spinal cord but the entire central nervous system works this way: internally generated activity is modulated by sensory input. In this view, the difference between being awake and being asleep is merely that the data coming in from the eyes anchors the perception.

Neuroscience over the next 50 years is going to introduce things that are mind-blowing.

Who we can be begins with our molecular blueprints - a series of alien codes penned in invisibly small strings of acids - well before we have anything to do with it. We are a product of our inaccessible, microscopic history.

Even while it's true that we are tied to our molecules and proteins and neurons - as strokes and hormones and drugs and microorganisms indisputably tell us - it does not logically follow that humans are best described only as pieces and parts.