The identity of a person or thing (or place or idea) is what distinguishes it from other people or things. In the special case of a human being, identity has two distinct uses. One use, which I shall call the public identity, refers to the identity of a third party and is generally composed of a full name, place of residence, and often an image of the face. The other use refers to the identity of the speaker or the audience. I call this the personal identity. In the following paragraphs I will be describing the personal identity, what it means to be you or to be me. Although "you" are included in this treatment of the term, the treatment is more applicable when you are considered from your own perspective, ie when you become the first person.

The essence of the personal identity can be broken into a piece based on the past and a piece based on the present. The piece that comes from the past is embodied in a person's memory. Some say that memory defines us, but it only defines one piece. The piece that comes from the present is embodied in the moment at which a choice is made. It is this present moment of choice that motivates my writeup. This is partly due to the fact that I have absolutely no control whatsoever over anything at all except for the present moment of choice. So in my capacity to act on my intentions, and in that capacity alone, I can define myself.

Often, my choice is to pay attention to another human being. When I see a person see something, I become them. When I read what they write, I become them. When I watch a smoker smoke, I become them and I feel the smoke enter my lungs, the drugs enter my brain, at least I imagine it, and I appreciate it, and I love it. And when I see someone seeing the smoker, being disgusted by it, I become them, and I am disgusted with it, with the damage to my lungs, the smoker's lungs, and it hurts me.

Sometimes I pay attention to memories I have of others, or I imagine what they will experience in the future or what they have experienced in the past. In this way, I am my children, my friends, their children, and all the descendants they will have. This joy I feel from the things I did yesterday, enhanced by my pride in having done them myself, is like the joy I feel from what my friends have done, or what they are doing now, enhanced by my pride in them for having done it. The joy I feel because of the smile given to me by a girl on the train yesterday morning, telling me that her husband does database development kind of like me, and the peanut butter cookies given to me by the boy sitting with her whose wife makes him cookies because she loves him is like it too. We share, and we become each other. Daylog, and we can become each other. I know that this body I inhabit will die, but because I have been Socrates, Lincoln, a poor wretch drowned in an unknown sea, and they have been me, I am compelled to determine how to fix the world. I will be around in the year 3000, 4000, 40000, to be all the people that lead us there, to enjoy this effort and its fruits.