Who you are depends on the sum total of your neurobiology.

...you are battered and bruised in the collisions between reminiscence and reality.

In the traditionally taught view of perception, data from the sensorium pours into the brain, works its way up the sensory hierarchy, and makes itself seen, heard, smelled, tasted, felt - "perceived." But a closer examination of the data suggests this is incorrect. The brain is properly thought of as a mostly closed system that runs on its own internally generated activity.

You are part of a complex social network that changes your biology with every interaction, and which your actions can change.

As Carl Jung put it, "In each of us there is another whom we do not know." As Pink Floyd sang, "There's someone in my head, but it's not me."

Scientists often talk of parsimony (as in "the simplest explanation is probably correct," also known as Occam's razor), but we should not get seduced by the apparent elegance of argument from parsimony; this line of reasoning has failed in the past at least as many times as it has succeeded.

If you cannot always elicit a straight answer from the unconscious brain, how can you access its knowledge? Sometimes the trick is merely to probe what your gut is telling you. So the next time a friend laments that she cannot decide between two options, tell her the easiest way to solve her problem: flip a coin. She should specify which option belongs to heads and which to tails, and then let the coin fly. The important part is to assess her gut feeling after the coin lands. If she feels a subtle sense of relief at being "told" what to do by the coin, that's the right choice for her.