rational naturalism is impossible!

[genkaus]

You're hijacking my example. I'm telling you that the caveman is running away from what he *believes to be a sack of potatoes dressed as a lion*. Therefore, the response is "run away", all the while the belief is "it's a sack of potatoes dressed as a scary thing". Survivability has been preserved while truth hasn't ergo survivability is independent of anything the caveman might believe to be true, which might include a false belief as to why a sack of potatoes is after him (i.e. he doesn't understand the creature is carnivorous).

Except, it doesn't make any sense for him run away from what he believes to be a sack of potatoes. If he believes that the thing in front of him is a sack of potatoes, then the response of running away makes no sense for him. The assumption that he'd, without any cause, regard the sack of potatoes as scary is unfounded. Regarding it as scary implies that he has knowledge of something similar that he has a legitimate reason to be afraid of - ergo, the knowledge of some other truth. At its core, the fear response is the result of true knowledge. Without it, survivability has not been preserved.

Which in that particular example happens to be that goblins hiding underneath lion skin are after him, thus producing the "arghh... scawey!" reaction out of him.

If the goblins are not going to harm him, then his survivability was never at risk - then the question of preserving it doesn't arise at all. If the goblins are going to harm him, then the belief that "that thing is dangerous" is true - thus, making survivability dependent upon truth. And if the goblins are really there to give him free food, then his survivability has been harmed by his false belief.

[Chas]

for my first post actually arguing for something, I decided to do something new. i'm using an argument I haven't seen here yet and one I think is very interesting. if you would like more details on it, it is an argument developed by Alvin Plantinga in my own reiteration.

instead of arguing a proposition is true or false, this argument concludes that it is impossible to rationally accept naturalism. here are the reasons for this:
1. P1 if naturalism is true, then there is nothing beyond our physical selves.
2. P2 evolution is a process that operates with the goal of survivability.
3. C1 our cognitive functions have come into being by the process of evolution- from P1&P2
4. C2 all our cognitive functions came about for the purpose of survivability which is not necessarily hinged on determining the truth- from P2&C1.
5. C3 we have no way to know if our reasoning leads us to truth in any proposition including the proposition of naturalism itself. any and all propositions based on our cognitive faculties (which are all of them) then are just as likely to be correct as they are to be incorrect- from P2&C2.

conclusion: it is impossible to rationally believe in naturalism. the very concept of naturalism entails the possibility of our cognitive faculties being unable to reason truth, which includes all truths including naturalism itself. it's self defeating. and before someone asks why this doesn't apply to religion like Christianity, the answer is P1 isn't a claim of Christianity and in fact is inconsistent with Christianity. if P1 is false, then C1 doesn't logically follow. a Christian can simply claim their cognitive faculties are indicators of truth by the intent of our designer.

extra notes- before i'm misunderstood I want to make it clear, this argument is not formulated to prove naturalism is false. I hope to see no one who interprets it that way. it is only meant to show how it is impossible to rationally believe it for the reasons in the argument. it shows that presupposing naturalism is true entails the best probability for all our beliefs to be correct is 50/50 since we can't know if our cognitive faculties are in fact indicators of truth. that is it.

P2 is not true, your argument fails.

[pocaracas]

C3 we have no way to know if our reasoning leads us to truth in any proposition including the proposition of naturalism itself. any and all propositions based on our cognitive faculties (which are all of them) then are just as likely to be correct as they are to be incorrect- from P2&C2.

Would this mean that my knowledge that if I drop a pen it will fall can be incorrect?

Sniff, sniff... I Smell a rat.... If the logic is not faulty, the premisses are.
And many people have told you that P2 is wrong... maybe they're right...

[Rational AKD]

there are a few responses I would like to respond to, though i'm not going to quote and address each specific person.
"P2 is false"
the only mechanism we have to determine what drives evolution is natural selection. this concept has not been disproven or improved upon as far as I know. therefore, any and all processes developed by evolution are done so by natural selection which by its own nature is survivability.
"survivability doesn't necessarily hinge on truth is false"
it doesn't. now i'm not making an extreme claim here. when I say it's not necessarily so, I mean it's possible and thus the 50/50 chance of it being so. but lets take for example matter. we all think objects are solid, but this may not necessarily be the case. it may have been possible for us to perceive the space between the particles of solid objects, but natural selection determines it's better for us to perceive it as solid. since such an example is conceptually possible, it is thus "not necessarily" hinged on truth.

a common objection many of you have is taking my argument to the extreme and saying things like "why would it be beneficial to survival not to see objects that are actually there?" i'm not speaking of those kinds of things. of course it's more beneficial to perceive what's actually there. but when it comes to logic and reasoning, these would be most affected because such things don't necessarily have to be true for the benefit of survival. in fact, this argument was originally developed from atheists who claimed religion came about by a process of natural selection because believing in a higher power was better for survival. the problem is, the same argument can be used against them.

how do creatures with lesser cognitive functions manage to survive? our cognitive functions are not necessary for survival, they're better for survival.
if I drop a pen... yes, you perceive it falling. perceptions through senses aren't really that subject to this argument. they may be to an extent, but perceiving things that are actually there is a necessary ability for survival. what would be most subject to this are abstract concepts like philosophical beliefs, naturalism included which is what makes it self refuting.

[genkaus]

"P2 is false"
the only mechanism we have to determine what drives evolution is natural selection. this concept has not been disproven or improved upon as far as I know. therefore, any and all processes developed by evolution are done so by natural selection which by its own nature is survivability.

Wrong again. Natural selection does not equal survivability. Otherwise features that impair survivability wouldn't be chosen for and yet many of them are.

"survivability doesn't necessarily hinge on truth is false"
it doesn't. now i'm not making an extreme claim here. when I say it's not necessarily so, I mean it's possible and thus the 50/50 chance of it being so. but lets take for example matter. we all think objects are solid, but this may not necessarily be the case. it may have been possible for us to perceive the space between the particles of solid objects, but natural selection determines it's better for us to perceive it as solid. since such an example is conceptually possible, it is thus "not necessarily" hinged on truth.

Are you ignoring the most obvious solution or do you simply not get it?

The ability to perceive the truth does not mean the ability to perceive each and every aspect of the truth out there. To the extent that we do perceive the truth, it aids our survival.

a common objection many of you have is taking my argument to the extreme and saying things like "why would it be beneficial to survival not to see objects that are actually there?" i'm not speaking of those kinds of things. of course it's more beneficial to perceive what's actually there. but when it comes to logic and reasoning, these would be most affected because such things don't necessarily have to be true for the benefit of survival. in fact, this argument was originally developed from atheists who claimed religion came about by a process of natural selection because believing in a higher power was better for survival. the problem is, the same argument can be used against them.

On the contrary, your ability to reason and use logic greatly aid your survivability.

how do creatures with lesser cognitive functions manage to survive? our cognitive functions are not necessary for survival, they're better for survival.

And as they are better for survival, they are chosen for by natural selection.

if I drop a pen... yes, you perceive it falling. perceptions through senses aren't really that subject to this argument. they may be to an extent, but perceiving things that are actually there is a necessary ability for survival. what would be most subject to this are abstract concepts like philosophical beliefs, naturalism included which is what makes it self refuting.

The ability to abstract concepts from perceptions is the next step which improves survivability by leaps and bounds. But once we have that ability, limiting its use for survival is not necessary.

[Faith No More]

As others have said, P2 is incorrect, which negates C2. There is no teleology to evolution. Mutations happen and they are either weeded out or ignored by natural selection. If they are detrimental to survival, they are more likely to be weeded out, and if they are more likely to be passed on if they are beneficial to survival.

Also, C3 doesn't take into account probability theory and our ability to determine what knowledge is more likely to be truthful than others. Rather than simply render all knowledge useless, naturalism requires us to determine the probabilities of certain knowledge. Just because we can't be certain about something doesn't mean we can't understand that that something is very likely to be true or untrue.

[Rational AKD]

Wrong again. Natural selection does not equal survivability. Otherwise features that impair survivability wouldn't be chosen for and yet many of them are.

what features would those be?

The ability to perceive the truth does not mean the ability to perceive each and every aspect of the truth out there. To the extent that we do perceive the truth, it aids our survival.

not really. the only thing that is beneficial to survival is to behave in a manner that is better for survival. this does not entail true beliefs.

On the contrary, your ability to reason and use logic greatly aid your survivability.

not epistemological reason. not metaphysical reason.

As others have said, P2 is incorrect

I suppose they will have to take that up with Richard Dawkins then. he writes in The God Delusion "since we are creatures of natural selection, we cannot totally trust our own senses." Daniel Dennett in Breaking the Spell claims "people have theistic beliefs only because they helped our ancestors survive difficult times." if this apparently applies to theistic beliefs, why not naturalism?

Rather than simply render all knowledge useless, naturalism requires us to determine the probabilities of certain knowledge.

if our cognitive faculties are developed for us to behave adaptively, why would our ability to determine probabilities be necessarily accurate?

[Faith No More]

I suppose they will have to take that up with Richard Dawkins then. he writes in The God Delusion "since we are creatures of natural selection, we cannot totally trust our own senses." Daniel Dennett in Breaking the Spell claims "people who have theistic beliefs only because they helped our ancestors survive difficult times." if this apparently applies to theistic beliefs, why not naturalism?

That is not what P2 claims. P2 claims that evolution operates with the goal of survivability, and that is not what Dawkins and Dennett are saying.

if our cognitive faculties are developed for us to behave adaptively, why would our ability to determine probabilities be necessarily accurate?

I don't follow. What do you mean by "behave adaptively"?

[Esquilax]

what features would those be?

The blind spot in the human eye, our spinal system which is maladjusted for life as a biped, our appendix, cancer, the donut shaped brain of a squid, the esophagus that passes right through the hole in that donut, the laryngeal nerve in a giraffe's neck, dew-claws on dogs, wisdom teeth, a dual-purpose urethra...

I could go on, if you need more.

Selection pressure isn't always upward, but it is always downward; the only criteria by which a trait survives natural selection is whether or not its lethally harmful to the organism possessing it.

[Rational AKD]

The blind spot in the human eye, our spinal system which is maladjusted for life as a biped, our appendix, cancer, the donut shaped brain of a squid, the esophagus that passes right through the hole in that donut, the laryngeal nerve in a giraffe's neck, dew-claws on dogs, wisdom teeth, a dual-purpose urethra...

I could go on, if you need more.

Selection pressure isn't always upward, but it is always downward; the only criteria by which a trait survives natural selection is whether or not its lethally harmful to the organism possessing it.

by that logic, developing true beliefs would not be a factor in lethal harm. P2 of the argument still stands.