"Who am I?" by Shawn Nevins:

You don't have to spend your days asking, "Who am I, who am I, who am I,..." Everything you do and everything that happens to you is asking that question for you. It's like the little kid who exasperates his parents by continually asking "why" -- "why is the sky blue, why is the grass green, why are we going here?" You are an immensely mysterious creature and a little curiosity about why you do the things you do, will carry you a long way on the spiritual path.

Did you ever watch yourself make a decision? I mean really watch what is going on in your mind. Let us say you don't know what to eat tonight. You think of some options, suddenly a decision is made. Did you decide or did a decision present itself? Were you just the observer of a process?

Did you ever try to catch the first thought of the morning? If you wake up slowly, you will find your mind quite silent. Suddenly there is a thought. Where did it come from? Did you decide it was time to start thinking, or did a process begin without your consent?

Some of our thoughts are obviously automatic. We might say, "It is hot," when the temperature is over 90 degrees. Other thoughts are equally reactive, but harder to trace. For example, we drive to the grocery to buy a chocolate bar when we are depressed, not because we really want it, but because the sugar gives us pleasure that counteracts the mood. Some people may enter relationships with the opposite sex for the same reasons as buying a candy bar, yet be just as unaware of the real reasons for their so-called decisions.

By examining the reasons for your actions, you are asking, "who am I." By watching your mind to see where decisions occur or thoughts arise, you are asking, "who am I." By simply being curious about your personality and wondering why you have certain likes and dislikes, you are asking, "who am I."

By becoming a watcher of your self, you are engaging in serious spiritual work. You are not that which is observed. You are the observer. If you are truly curious and diligent, you will find you can observe your observing. Here you run into a roadblock -- the mind watching the mind.

The mind continues to watch decisions being made, thoughts occurring, and at times watches itself watching. And perhaps, in watching the watching, a great doubt descends as we realize we are watching all that we know, yet feel a hint of something more -- beyond our knowing. Beyond knowing, where words fail, where our self fails, where we lose all to become All.

http://www.tatfoundation.org/forum2001-01.htm#5