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by _nothing 1623 days ago
I don't think you're a creationist - this is just a very common distinction in thinking about evolution that results in all sorts of illogical fallacies.

This is my exact point: Your hands have no purpose. They evolved in a way that aided in survival. If someone is born mutated with their fingers fused together and then suddenly the entire earth floods and they find their solid hands help them swim better - were their hands evolved for the purpose of swimming? Were they designed? Is that human then "supposed to" swim?

We're finding microorganisms that can consume plastic. Does that mean they evolved for the purpose of eating plastic, a substance not typically found in nature?

In my worldview, no, they weren't. They can consume plastic, but that has no bearing on their purpose, and they aren't leaving part of their purpose unfulfilled if they don't eat plastic and instead eat other substances they evolved to be able to eat.

3 comments

Your scenario with mutated hands ignores that evolution is about selection, not just single mutations. If hands evolved over a period of millions of years to be able to push water better, you could indeed say they evolved for the purpose of swimming. This is similar to saying that an eye’s purpose is to see, or a heart’s purpose is to pump blood, which are hardly controversial statements.

A purpose doesn’t have to imply concious design, intent, or immutablity.

You're making assumptions and taking the conversation in a pedantic direction.

I am aware of the nature of natural selection and how it builds complexity over time through various selection pressures not all of which are constantly aligned with end result. And although wings were initially little nubs not "designed" for flying you could say that wings are they are now are "designed" for flying.

"Design" and "purpose" as I've said many times throughout this thread is a word that flows better. It is a linguistic choice and you are taking the argument in a direction thinking I don't understand some trivial point about natural selection.

I’m not really sure why you bothered to reply, my comment had nothing to do with you. I was just pointing out the flaws in the scenario the parent comment presented.
Thats an interesting point but I think I'd have to disagree - purpose is very much constrained to concious design. Those traits were selected not for the purpose of swimming but merely due to the pressure of selection itself. In your example of flippers, the selection pressure is likely on mobility but the purpose of a limb is not mobility in and of itself. Would that make a flipper purposeless if moving over land?
Those traits would be selected because being able to swim increases survival. The purpose is survival via swimming.

To put it another way, the fact that the inputs (mutations) are random does not mean the outputs have no purpose.

If I said “the purpose of eyes is to see”, would you really disagree with that?

Also, it is entirely possible for body parts to have multiple purposes, that is quite common.

>purpose is very much constrained to concious design.

Not true. Natural selection can produce the same results as artificial selection. They are both effectively the same process where in one scenario the guiding hand is human and the other scenario nature is the guiding hand.

If both nature and artificial selection evolved a mechanism that is very specifically and efficiently able to do one thing and one thing only does it mean that the thing evolved has no purpose? No it doesn't.

Either way we're getting into a linguistic and philosophical argument on the meaning of the word "purpose." These are traps. Ultimately we begin arguing about the definition of an ambiguous word thinking that the argument is profound. It's like all those arguments about "What is life." Pointless, "life" is the word that is loaded and ambiguous; any debate of that nature is simply an argument about the intricacies of a vocabulary word.

This is pedantic. Everybody knows about evolution and natural selection and the intricacies behind the process, it's old news.

Energy flows into and out of a system in a way where the configuration of particles begins arranging itself in lower and lower entropy formulations. The net entropy of the universe remains forever increasing but within this system it begins lowering. One of these low entropy formulation begins self replication imperfectly thereby introducing memory and mutation into the system allowing complexity to build on itself thereby producing particle configurations of immense low entropy and complexity.

Is there any "intent" in the description above? No. But you must consider the factor below:

Clearly your hands weren't designed with an intelligent intent. Yet there is something different about your hand then there is a rock. What is the word used to describe this difference? "Design" flows better, that's it, no need to get into "illogical fallacies."

>We're finding microorganisms that can consume plastic. Does that mean they evolved for the purpose of eating plastic, a substance not typically found in nature? >In my worldview, no, they weren't. They can consume plastic, but that has no bearing on their purpose,

I don't know if you can see this, but your argument here is not profound. You are making a linguistic argument. You are arguing for the definition of the word "Purpose" or "Design." We BOTH know EXACTLY what is going on with natural selection and "design" is simply an easier way to express a point that your hand is a lower entropy configuration of atoms that is clearly very efficient at grasping things. But my previous sentence is an inefficient way of saying it. I could just say your hand is designed for the purpose of grasping things and the rock is not.

I think this point is very hard to argue against. Natural selection has no intent, mutation is random and its consequences are thus flukes as to whether they work or not to support an organisms survival. Very well explained @_nothing!
Their post missed the fact that evolution is about selection, not just single mutations.
No it doesn't. You're just assuming such.
They described a scenario where someone was born with mutated hands that happened to be useful for swimming after the earth floods. There’s no selection or evolution there.