Different in degree or kind: EVOLUTION (Introduction)

by dhw, Thursday, January 08, 2015, 19:46 (3607 days ago) @ David Turell
edited by dhw, Thursday, January 08, 2015, 19:57

dhw: The key to this is common descent. As you yourself have repeatedly pointed out, bacteria remain unchanged, and so multicellularity and evolution itself could not have been a matter simply of improving “survivorship”. There must be some kind of drive towards improvement for its own sake, and that - as reflected in our own human culture - is a purpose in itself. ....And so the history of startling improvements is not from apes to humans but from bacteria to humans, and NONE of these changes were “needed”.-DAVID: You have drawn out all the reasons for seeing purpose, and then stop short. I see no reason for the developments following a set of naturalist thoughts. Life appeared against all probability, bacteria have lived unchanged forever, multicellularity was not needed, but sexual reproduction introduced a better way to change and/ or improve DNA. Again, all I can see is purpose, purpose, purpose. Everything I've listed is against enormous odds. I still see underlying this only chance or design.-You are repeating my own arguments! You said that human intelligence was not necessary for the survival of the apes, and I pointed out that NO evolution was “necessary”, since bacteria have survived unchanged. And so humans can't be special just because they were not needed! You cry purpose, purpose, purpose, but the only purpose you can think of is the creation of humans. I point to survival and improvement, but you can't see that these constitute purposes - even though you are confronted with them every day of your life. -dhw: That is not an argument against God, as it doesn't explain the source of the mechanisms for improvement, but it seems to me to invalidate the claim that humans are “special creations” because their abilities were not needed for survival.
DAVID: Here we strongly differ. Humans developed without any reason. They appeared against all odds.-Same again: all life appeared against all odds. If humans developed without any reason, so did all multicellular forms, since bacteria have survived without evolving. But if we accept improvement as a reason for evolution, it applies to all multicellular forms, including humans.-dhw: If humans weren't “needed”, nor were any of the organs and organisms that evolved from the first cells, and all species remain unchanged until they go extinct, or branch out following innovations! 
DAVID: Exactly!!! There is obviously a drive for improvement as you have stated. Because the successful bacteria didn't have to improve. We know that. You simply bring up improvement for its own sake, whatever that means.-Every organism tries to survive. That is one purpose. I'm suggesting that when the opportunity arises, organisms also try to improve. At one time or another there was no sex, there were no legs, no eyes, no ears, no brains, no teeth, no fins, no wings....They were not needed for survival. But if you believe in common descent, every single innovation must have taken place within existing organisms, and whether your God started the whole process off or not, these innovations improved the organism's ability to cope with its environment. That is a purpose! Other organisms still survived without them, and so in that sense they were not “necessary”.
 
DAVID: To me you seem to stop thinking when the obvious issue of purpose is presented. Do you deny the marked impression of purpose in the course of evolution?
-On the contrary, I have emphasized the twofold purposefulness of its developments: survival and improvement. What you are so desperately looking for is an overall purpose, and you insist that this is the production of humans. Organisms had to produce wings and fins and trunks and humps and rattles and compound eyes and strange migratory patterns and other weird and wonderful lifestyles, and go extinct by the billions, just so that we humans could walk the Earth. The issue between us is not whether evolution is purpose-driven, but the fact that you are only prepared to consider ONE possible purpose.