Tuesday, July 29, 2008
The Problem of Purpose (part 1)
As humans, we like to think that everything has a purpose. And certainly, nature doesn't contradict that view: peacocks' tails exist to attract peahens, cats have claws so that they can kill mice, birds sing to mark their territories and attract mates, humans have a big brain which enabled the species to develop advanced technologies, cockroaches--okay, maybe those don't have a purpose. The point is that animals exist in certain shapes and forms for reasons, presumably to better fulfill their "destiny", to live out their "purpose".
Except this assumes that some force (the Guiding Hand of God, perhaps?) was directing a small furry mammal to become say, a lemur, and then the lemur to become an ape, and the ape to become a human. It assumes that there was a reason for the animal to evolve along the lines it did.
Scientists make this mistake a lot, actually. Genetic studies purporting to demonstrate why we are genetically predisposed to becoming obese, the link between abnormal proteins here and Alzheimer's/schizophrenia/drug addiction there, and sickle cell anemia and resistance to malaria, must be very careful not to ascribe the selection pressures for a particular gene as the purpose for the gene's existence. Genes exist, solely because the vehicle they are temporally transferred in (living creatures) managed to live long enough to pass it on. No lemur decided, "Hey, this tree-climbing thing is sure getting hard out here on the savanna. I think I'll evolve bipedalism!"
The fact is, there really is no reason for anything to exist, other than the fact that it's not dead already. And this, I think, is one of the biggest problems creationists have with evolution.
It is a stark picture: you exist only because your parents didn't die before they had you. There is no purpose to your life, no "reason" why you were born in the body that you have and with the brain that was given to you. No wonder creationists have such a problem with evolution: it runs counter to everything religious and/or spiritual belief we might have concerning our existence on this planet.
Natural selection is the reason why we evolved the way we did--God, if He's indeed out there, didn't coax anything along except death, destruction, and mayhem. One could hypothetically argue that He, in His divine might, decided that thus would be the vehicle by which He created all life, but that doesn't really change the essence of the argument: natural selection is a harsh and fickle mistress.