Who Are You ?
What is your essence? Is it matter—a mere collection of material atoms and molecules? Or is it something else?
"Who am I?" Maybe you've never even asked yourself this question. You might think you already know who you are. Unfortunately, however, it's likely that you don't know who you are at all. And if you don't know your real identity, you're in trouble. You'll spend your life in a kind of dream state—you'll falsely identify yourself as something or someone you aren't. Then, on the basis of this false identification, you'll determine the goals of your life and the purpose of your existence. You use these goals to gauge whether you are making "progress" in life, whether you are a "success." And you are aided and abetted in this delusion by a complex network of relationships with other dreamers. Of course, at death (and sometimes before), the whole thing turns into a nightmare.
So knowing who you are is a very practical necessity. The question "Who am I?" is not a philosophical football meant to be kicked around coffeehouses by pseudo-intellectuals. It's a real-life question. Nothing is more important and more relevant than to know who you are.
You are your body, right? You are chemical in essence ... right? At least, that's what one of America's most influential scientists claims:
"I am a collection of water, calcium and organic molecules called Carl Sagan.
You are a collection of almost identical molecules with a different collective label."*
Like Sagan, most people believe that they are their body. So if you ask them who they are, they think and respond in terms of bodily labels.
"I'm Susan. I'm blond, 29 years old, a mother, and still 36-24-36!"
"I'm Henry. I'm a white American male and proud of it!"
"I'm John. I'm a lawyer. I'm 40 years old and getting older every day."
"I'm Alice. I'm a female student. I'm fat and I'm a Methodist."
Name, race, age, sex, religion, nationality, occupation, height, weight, and so on—all these are bodily labels. Therefore if you consider your body to be yourself, you automatically identify yourself with such labels. If your body is fat and ugly, you think, "Woe is me! I am fat and ugly." If your body is 60 years old and female, you think, "I am a 60-year-old female." If your body is black and beautiful, you think, "I am black and beautiful."
But is the body really the self? Are you really your body?
*Carl Sagan,Cosmos (New York: Random House, 1980), p. 127.
Let me ask you a few simple questions: Do you exist at this moment? Did you exist five years ago? Are you your body? Most people would answer "yes" to all three questions. But if you identify your body as yourself, and simultaneously accept that you exist now and also existed five years ago, then you have a problem: The body you had five years ago does not exist today. There is a dynamic turnover of atoms and molecules which make up your body. There isn't a single particle of matter—not one atom—present in your body today that was present five years ago. The body you have today is not the same body you had five years ago. It's not that the body you had still exists but has now changed somewhat. No. The body you had is gone. That collection of atoms appearing as flesh, bone, blood, hair, and so on no longer exists. Yet you still exist.
The physical body is made up of countless numbers of tiny material particles called molecules and atoms. These material particles are constantly being replaced by material particles from the outside environment (in the form of food, water, air, and so on). Over a period of five to seven years, this process of metabolism brings about a complete change of the matter that makes up your body.
Recent studies at the Oak Ridge Atomic Research Center have revealed that about 98 percent of all the atoms in a human body are replaced every year. You get a new suit of skin every month and a new liver every six weeks. The lining of your stomach lasts only five days before it's replaced. Even your bones are not the solid, stable, concrete-like things you might have thought them to be: They are undergoing constant change. The bones you have today are different from the bones you had a year ago. Experts in this area of research have concluded that there is a complete, 100 percent turnover of atoms in the body at least every five years. In other words, not one single atom present in your body today was there five years ago.*
* Taken from Guy Murchie,The Seven Mysteries of Life (Boston: Houghton-Mifflin, 1978), pp. 321-22.
Many people believe that a person is the brain or some part of the brain. You may be one of them. If so, the following should boggle your mind:
Recent studies on the turnover of the molecular population within a given nerve cell have indicated that ... their macromolecular contingent is renewed about ten thousand times in a lifetime.*
In other words, the matter making up each brain cell is completely renewed every three days.
Your brain—that mass of matter which is contained in your skull today—is not the same brain that was in your skull last week.
*Paul Weiss, "The Living System: Determinism Stratified," in Arthur Koestler and J.R. Smythies, eds.Beyond Reductionism (London: Hutchinson, 1969), p. 13.