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Evolution is descriptive, not prescriptive

It's not clear to me that the posters quoted made the naturalistic falacy, but the first one either did or replied with a non-sequiteur: "if you think X is wrong, how do you justify Y, which necessarily entails X?"
"Simple, Y is healthy."

The second quote includes the following: "People can choose to eat whatever they want but just don't try convincing me that I'm doing the "wrong" thing by eating meat and I'm fine with vegans/vegetarians/etc." after saying "humans evolved to be omnivores.
It seems to me he's saying "we evolved to be omnivores, so eating meat can't be wrong."
If that's the point, then the OP is correct. However, the wording is loose enough that I may be misreading it.
If I'm misreading it, the only other option I see is that he's saying "eating meat in moderation is healthy. I'm not interested in talking about moral issues (which are separate)."
 
Again, take your own advice.
I've not insulted you so there is no advice to take.


Does evolution teach us we should prohibit sexual abuse or not?
Evolution doesn't teach us anything. I never said that it did.
  • Humans have empathy.
  • Humans have compassion.
  • Humans have mind theory.
  • Different parts of the human mind are pre-wired, based on evolution, for certain moral sentiments.
These are all evolutionary based and we can understand why we behave in a moral manner if we understand them. Understanding can help inform our moral reasoning.

Using MRI's and by asking various questions we can see that there is moral ambiguity and dilemma within any given human mind that is not easily reconciled.

My point is that we can't simply dismiss evolution and our genetic predispositions when it comes to moral reasoning.
 
drkitten;4035001 said:
Let me repeat, so that there's little possibility of misreading.
Princess's OP is wrong beyond the possibility of repair.


Repeating it doesn't make it true. I think you missed something in the OP, which was Princess citing others who think that merely because evolution made us omnivores, we should be omnivores.

I take it Princess woiuld cite the availability of artificially produced vitamins or amino acids may well mean we do not need to use some species as food that we otherwise evolved to do so.

Compare with pregnancy and sex. Sex was evolved for the sake of pregnancy; does that mean those of us who can should get preggers, or that we should only use sex for pregnancy? Or if you want to cite sex for bonding, does that mean we should only use sex for bonding? Are contraceptives against Nature?

Your argument is similar to those who claim natural law and evolution mean homosexuality is "wrong".

"Evolution made us omnivores" is not a statement about how humans "should" behave, nor does it carry any moral weight whatsoever.

Bingo. But Princess was tackling those who do think that such a statement about evolution is also a normative statement, a statement about how we should behave.

Should homosexuals stop being homosexuals? Does homosexuality or a vegetarian diet with vitamin/ amino_acid supplements go against nature?


On the other hand, if you feel (independently) that people should act efficiently (there's Hume's "should"),


That is only saying if you adopt a moral viewpoint then you should proceed with that moral viewpoint.

You do get that Hume showed you cannot get from an empirical statement (is) to a moral statement (should) logically, don't you?

then it's reasonable to infer from the observational fact that meat consumption is the most efficient way to get needed amino acids, that humans "should" consume meat.

All you did was infer a course of action from a moral (utilitarian) statement.

And Princess's OP is wrong beyond the possibility of repair.

Wrong. And the category error is yours. All Princess has done is to reiterate you cannot make moral statements logically derived from empirical statements, something which you yourself have admitted, so it's rather peculiar you should claim Princess is wrong.
 
It's not clear to me that the posters quoted made the naturalistic falacy, but the first one either did or replied with a non-sequiteur: "if you think X is wrong, how do you justify Y, which necessarily entails X?"
"Simple, Y is healthy."

That's not a non-sequitur. If something is wrong-but-healthy, that is a sufficient justification for someone who desires and cares about health more than they care about moral purity.
 
......
  • Humans have empathy.
  • Humans have compassion.
  • Humans have mind theory.


Only some do. And humans differ on morals. So just what significance does your statement about evolution have? None.


  • Different parts of the human mind are pre-wired, based on evolution, for certain moral sentiments.

Goodness. Now there is a mightily overly ambitious claim. You must now explain why humans show such different moralities, and why humans are capable of changing their morality.

Or, IOW, to repeat: your original statement was only trivially true at most, and explained nothing,

These are all evolutionary based and we can understand why we behave in a moral manner if we understand them. Understanding can help inform our moral reasoning.

"Moral reasoning"???? First you claim hardwiring regarding morals, then you bring in moral reasoning? Begin yet to see the confusion in your thinking?


My point is that we can't simply dismiss evolution and our genetic predispositions when it comes to moral reasoning.

That wasn't your original point at all, and it's totally irrelevant, since no-one here is dismissing evolution or its predispositions at all.

What is under dispute is your dispute with the OP, and your vague claims about evolution determining morality.

I notice you did not tackle the examples I gave you; and predispositions do not equal determination.

Or, IOW, Princess' OP was spot-on, in logic as well as science, so do you in actual fact have any argument leftat all?
 
Your morality is the result of evolution. That you have a moral sense is because of evolution. Much of why you sense what is moral as moral is the result of evolution. Saying evolution is not a moral theory is not saying anything. It's like saying that human progress isn't natural or the result of evolution.
But what does that have to do with OP. The OP is saying "us being natural omnivores doesn't mean that eating meat is morally justifiable - the two are separate issues." At least, that's how I read it.
Saying that our moral sense evolved doesn't suggest differently.

BTW, evolution has made us omnivorous. That's trivially true. It's not a moral justification for eating meat but denying that is rather silly.
I don't see that anyone has denied that evolution has made us omnivores.
From my reading of the OP all she's saying is exactly what you just said - that evolution made us omnivores isn't a moral justification for eating meat.

It is believed that eating meat is the reason we gained the degree of cognitive ability that we have. Ironic that eating meat gave us the ability to choose not to eat meat.
Ironic, yeah. Not that we know that this hypothesis is correct (I personally think it's somewhat likely, but from what I know it's not something we've really confirmed very well at this point - correct me if I'm wrong).
And I don't think it has much to do with the OP.
 
....[snip]

Evolution is not a moral theory.
I'm quite sure skeptics would not be arguing that evolution is a moral theory. Could you post an example from the forum where skeptics here have taken that position?

I'm not sure how your examples from Talk Origins demonstrate anyone from that site is making the argument evolution theory is a moral theory. To the contrary, it is laughable when people like Ben Stein make the claim evolution theory was partly (or wholly) responsible for Hitler's extermination of the Jews and other groups of people. The theory says nothing about actions people should or shouldn't take based on the knowledge the theory provides.
 
That's not a non-sequitur. If something is wrong-but-healthy, that is a sufficient justification for someone who desires and cares about health more than they care about moral purity.

All you are doing is introducing value choices, then claiming somehow your value choices prove the OP wrong.

Princess' point was: you cannot get from a description of nature to a prescriptive (normative) statement logically.

IOW, Princess is saying you cannot say a description of what is then makes a moral statement, you cannot get from an is to a should via logic.

Your point? You claim that if you make a certain value choice, then a course of action is clear.

Amusingly, that was exactly what Hume tackled, the fact that as he observed in any such attempts, a hidden moral statement was introduced into the initial premises, and then it was pretended one got from an is to a should logically.
 
Hume (mods, the below is not subject to copyright):

I cannot forbear adding to these reasonings an observation, which may, perhaps, be found of some importance. In every system of morality, which I have hitherto met with, I have always remarked, that the author proceeds from some time in the ordinary way of reasoning, and establish the being of a God, or makes observations concerning human affairs; when of all sudden I am surprised to find, that instead of the usual copulations of propositions, is and is not, I meet with no proposition that is not connected with an ought, or an ought not. this change is imperceptible; but is, however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation, 'tis necessary that it should be observerd and explained: and at the same time that a reason should be given, for what seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it. But as authors do not commonly use this precaution I shall presume to recommend it to the readers; and am persuaded, that this small attention would subvert all the vulgar systems of morality, and let us see, that the distinction of vice and virtue is not founded merely on the relations of objects, nor as perceived by reason.

--- from A Treatise of Human Nature, (1739-40), Book III, Part 1, Section 1, p. 469-470, by David Hume
 
That's not a non-sequitur. If something is wrong-but-healthy, that is a sufficient justification for someone who desires and cares about health more than they care about moral purity.
Fair enough, I suppose I'm just objecting to the fact that he didn't say "health is more important to me that the (perhaps rather small) moral concern of the suffering - or whatever - involved in eating meat".
The point being that it didn't even consider addressing the moral issue. I suppose I can agree though that there's the implied answer that you suggest - that the moral issue is less important than the health issue.
 
But what does that have to do with OP. The OP is saying "us being natural omnivores doesn't mean that eating meat is morally justifiable - the two are separate issues." At least, that's how I read it.

Saying that our moral sense evolved doesn't suggest differently.
It's a bit complicated.

Nazca Boobies evolved to kill their siblings. It's obligate of them for survival. We tend to react in shock to that but it's really quite possible that humans could have evolved obligate siblicide and that would be moral for us. We know that morality is not a priori so how do we reason what is moral? What are the base premises and how do we make our decisions? It's not simple and stating that evolution is not a moral theory doesn't help. No, it's not a moral theory but moral theory is requisite of evolution and we would best reason moral theory by understanding evolution underpinnings of morality.

a.): A runaway trolley is hurtling down the tracks toward five people who will be killed if it proceeds on its present course. You can save these five people by diverting the trolley onto a different set of tracks, one that has only one person on it, but if you do this that person will be killed. Is it morally permissible to turn the trolley and thus prevent five deaths at the cost of one? Most people say yes.

b.): Once again, the trolley is headed for five people. You are on a footbridge over the tracks next to a large man. The only way to save the five people is to push this man off the bridge and into the path of the trolley. Is that morally permissible? Most people say no.

Why do we see the two hypotheticals differently when the outcome is the same? It turns out it is because different areas of the brain are involved in making these moral decisions.

You can state that evolution is descriptive but if evolution renders some people sociopaths then their morality is different from the norm. He or she can know that society holds that harming others is wrong but that is incidental to his or her morality.
 
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It's a bit complicated.

Nazca Boobies evolved to kill their siblings. It's obligate of them for survival. We tend to react in shock to that but it's really quite possible that humans could have evolved obligate siblicide and that would be moral for us.
I don't accept that. As the OP pointed out, rape may be an evolved behavior, but that doesn't make it moral.
Another, less polarizing, example is incest. Incest avoidance, and in particular, our sense of disgust toward incest, is evolved (well, I think the evidence that it is is strong enough to say this, anyway). But that doesn't in itself mean that incest is wrong. Personally I have no problem with a brother and sister marrying if they want to, in particular if we avoid the other possible complication (for instance, if they are sterile).
If it's possible that incest isn't immoral, then morality derives from something more complex than a moral sense.
I admit that it is influenced by an evolved moral sense. But that doesn't mean that something being evolved is an argument for it's morality.

We know that morality is not a priori so how do we reason what is moral? What are the base premises and how do we make our decisions? It's not simple and stating that evolution is not a moral theory doesn't help.
I think it helps quite a bit. It means we avoid the mistake of saying "since rape evolved, it must be good".

No, it's not a moral theory but moral theory is requisite of evolution and we would best reason moral theory by understanding evolution underpinnings of morality.
Sure, but some of the insight that can give us is into the mistakes we make due to that evolved moral sense. For instance, in demonizing outsiders.

a.): A runaway trolley is hurtling down the tracks toward five people who will be killed if it proceeds on its present course. You can save these five people by diverting the trolley onto a different set of tracks, one that has only one person on it, but if you do this that person will be killed. Is it morally permissible to turn the trolley and thus prevent five deaths at the cost of one? Most people say yes.

b.): Once again, the trolley is headed for five people. You are on a footbridge over the tracks next to a large man. The only way to save the five people is to push this man off the bridge and into the path of the trolley. Is that morally permissible? Most people say no.
I agree that my gut reaction is the same as most people, except that I'm a little slow to say no to the second.
But that only suggests that my gut reaction is evolved (which I agree with anyway). It doesn't suggest that my gut reaction is right.

Why do we see the two hypotheticals differently when the outcome is the same? It turns out it is because different areas of the brain are involved in making these moral decisions.
Yeah, and the cool thing is that the more that we understand these things, and the ways we go about making moral judgements, the more, in my opinion, we can use our understanding to improve our morality.

You can state that evolution is descriptive but if evolution renders some people sociopaths then their morality is different from the norm. He or she can know that society holds that harming others is wrong but that is incidental to his or her morality.
I would suggest that this person is not moral, in spite of working under a different moral system. I suggest that his moral system is simply wrong.
 
Princess' point was: you cannot get from a description of nature to a prescriptive (normative) statement logically.

That wasn't all of Princess' point. She further claimed (wrongly) that the readership of the forum was attempting to do so, and criticized (unjustly) the rest of the readership for not slapping them around for doing so.

Here's the direct quote:

Princess said:
Seriously, people, this is a critical thinking messageboard. No one, apart from a few of the vegetarian members of this forum, corrected those posters on their uncritical comments.

The problem is that the comments cited weren't "uncritical" and so no correction was needed or even appropriate.

IOW, Princess is saying you cannot say a description of what is then makes a moral statement, you cannot get from an is to a should via logic.

No, she's saying that people tried to do that, and chastised us for permitting it.

Your point? You claim that if you make a certain value choice, then a course of action is clear.

Amusingly, that was exactly what Hume tackled,

Not that amusing. I've read Hume before. I've even understood him, which apparently is more than you have.

And, no, that's wasn't my point -- having read Hume, I find him vacuously verbose, and not worth the effort to regurgitate. My point was that Princess is imagining moral content in observations where there is none. Such as "evolution has made us omnivores," which again is exactly as morally binding as the observation that "evolution has made us bipedal." If for some reason, you find bipedalism morally distasteful, there are solutions. For most people, the convenience of bipedalism will (implicitly or explicitly) trump any moral qualms they have about it.
 
Repeating it doesn't make it true. I think you missed something in the OP, which was Princess citing others who think that merely because evolution made us omnivores, we should be omnivores.

And the reason that I missed it is because Princess made no such citations; her citations were entirely erroneous and she's making false accusations.

Bingo. But Princess was tackling those who do think that such a statement about evolution is also a normative statement, a statement about how we should behave.

... and since there's better evidence for leprechauns than for readers on this forum who think in that way, I see no reason to support her in this "tackling."

She can argue with all the imaginary strawmen she likes in the privacy of her own mind. I feel no moral compulsion to support her crusade in the shared reality of the Internet.
 
BTW, good post and thanks for the tone. These issues really touch buttons. It's really not my intention to be provocative.

I don't accept that.
You "don't accept that"? Are you saying that killing one's sibling is a priori wrong?

As the OP pointed out, rape may be an evolved behavior, but that doesn't make it moral.
No one says that it does. That isn't an answer though. Rape isn't a priori wrong. You are looking at the world through the filters of your morality and then post hoc rationalizing your view of what is and isn't moral. Just because you and I might have a moral sense that rape is wrong doesn't make it wrong.

If I'm wrong then you need to form a coherent argument that stands apart from our moral sentiment. Can you do that?

Another, less polarizing, example is incest. Incest avoidance, and in particular, our sense of disgust toward incest, is evolved (well, I think the evidence that it is is strong enough to say this, anyway). But that doesn't in itself mean that incest is wrong. Personally I have no problem with a brother and sister marrying if they want to, in particular if we avoid the other possible complication (for instance, if they are sterile).
If it's possible that incest isn't immoral, then morality derives from something more complex than a moral sense.
I don't understand your argument (point).

I admit that it is influenced by an evolved moral sense. But that doesn't mean that something being evolved is an argument for it's morality.
I've not said anything so simple.

I think it helps quite a bit. It means we avoid the mistake of saying "since rape evolved, it must be good".
I'm not making this argument. I understand your point. I assure you it's not my intent to rationalize behavior purely through evolution. I've never done that here.

That said, it's isn't helpful because it ignores why and how we have a moral sense. If human survival relied on our killing our siblings we would have evolved a sense that it is moral. And it would be moral. That is trivially true.

Your stance seems to assume that morality is a priori. It's not.

Sure, but some of the insight that can give us is into the mistakes we make due to that evolved moral sense. For instance, in demonizing outsiders.
I know it's complicated but I'm not saying that we should justify behavior based on evolutionary traits. Only that we can understand the context of our morality.

I agree that my gut reaction is the same as most people, except that I'm a little slow to say no to the second.

But that only suggests that my gut reaction is evolved (which I agree with anyway). It doesn't suggest that my gut reaction is right.
:) Thank you. The smilie is there only because you are the first person to respond.

Here is the important question: Why isn't your gut reaction right?

Before you answer it, consider the next hypothetical. Sorry.

You are on a bus full of passengers behind enemy lines during a war. It is known that the enemy kills enemy civilians so caught. A baby is crying and all efforts fail to muffle the cries or get the baby to stop. Do you kill the baby to save everyone else? (that's not really the important question). Here's the thing. Women as a group are the most likely to say no. People who have had children are more likely to say no. People, especially men, who have not had children are morel likely to say yes.

Here is the next important question to consider with the first: Don't you bring your perspective and genetic predisposition to bear on the problem? If you knew that there are different parts of the brain that fire (stastically) depending on gender and/or whether a person has a child or not. Does that come to bear on the dilemma?

Yeah, and the cool thing is that the more that we understand these things, and the ways we go about making moral judgements, the more, in my opinion, we can use our understanding to improve our morality.
I couldn't agree more. Yes.

I would suggest that this person is not moral, in spite of working under a different moral system. I suggest that his moral system is simply wrong.
? Wrong compared to what?

So you do believe that morality is a priori? It must be. That is the only way you could come to this conclusion.
 
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BTW, good post and thanks for the tone. These issues really touch buttons. It's really not my intention to be provocative.
Thanks - I didn't think you were being provocative at all. I was concerned at one point that I might be if I used the rape example given in the OP (which is why I tried to find something less emotional).

You "don't accept that"? Are you saying that killing one's sibling is a priori wrong?
Not exactly. I think that some things are a priori wrong, but a higher order action like killing a sibling needs to be put into a context. I would say that to say "killing siblings is wrong" is similar to saying "rockets are powerful". As you say, "powerful compared to what?".
Sure, most rockets are powerful, and we can usually figure that killing siblings is wrong, but there are some toy rockets that barely get off the ground. We need the context.
On the other hand, I can say something like "nuclear reactions are more powerful than chemical reactions", and that's something that is true regardless of context (and continues to be true even in situations where I can derive more power from a chemical reaction, simply because there's more of the chemical).
Okay, so... basically I'm saying that there are a priori moral truths (in my opinion), but they are basic things like "pleasure is good".

No one says that it does. That isn't an answer though. Rape isn't a priori wrong.
I agree, but there are situations where if you look at the context, and understand what is a priori right or wrong, then no matter who you are, you will be forced to conclude that in that situation it was wrong.
You are looking at the world through the filters of your morality and then post hoc rationalizing your view of what is and isn't moral. Just because you and I might have a moral sense that rape is wrong doesn't make it wrong.
I agree. I think that's one of the biggest problems with my moral system. I take my preformed morality and perhaps try to justify it with first principles, rather than starting from first principles and coming to a fully formed moral system. That moral system would likely look much different from the one I use.
On the other hand, what I can do is take those "first principles" and apply them to my preformed morality, and if it comes up short, discard aspects of it. I think that's better than nothing, anyway.

If I'm wrong then you need to form a coherent argument that stands apart from our moral sentiment. Can you do that?
I think so, but I don't think it's complete.
I'll try to put it out in another post.

I don't understand your argument (point).
To be honest, I think it was me he who didn't quite understand your point, so I replied on a tangent.
Anyway, I was just saying that from my perspective we have to apply something more complex than emotion to form moral judgement. It's not enough to say 'this feels wrong' in order for it to be so. If morality were based on that, it would be no more justified to do what is "right" and oppose what is "wrong" than any other course of action. Choosing between going to a prostitute (because it feels good) and doing charity work (because it feels good) would be the same sort of choice.

I've not said anything so simple.

I'm not making this argument. I understand your point. I assure you it's not my intent to rationalize behavior purely through evolution. I've never done that here.
Agreed, I apologize for misreading you.

That said, it's isn't helpful because it ignores why and how we have a moral sense. If human survival relied on our killing our siblings we would have evolved a sense that it is moral. And it would be moral. That is trivially true.
I accept that we would have evolved a sense that it is moral, but not that it would be moral. Human survival relied on our violent animosity toward pretty much any social group that wasn't closely related to us. In my times and places that's been considered moral. But I think you and I agree that here and now it is not.

Your stance seems to assume that morality is a priori. It's not.
This is where we disagree. Or almost. I'll have to outline my opinion in another post. But basically I suggest that we all make basic moral assumptions about ourselves. I only think that we should apply fairness and see what about ourselves we think gives us moral standing and then apply the same moral standing to anyone who shares those qualities.
Those who make no moral assumptions about themselves (who don't view themselves as having moral standing) are free of this requirement. So in a way morality isn't a priori, but since I think pretty much everyone does make those assumptions, it practically is.

I know it's complicated but I'm not saying that we should justify behavior based on evolutionary traits. Only that we can understand the context of our morality.
In that case I apologize for misreading you. I agree with you, quite strongly, about that. :)

Here is the important question: Why isn't your gut reaction right?
Because there is nothing intrinsic to my gut reaction that should give it value. It could be anything. That it happens to lead me one way doesn't suggest that that has any moral value.

Before you answer it, consider the next hypothetical. Sorry.

You are on a bus full of passengers behind enemy lines during a war. It is known that the enemy kills enemy civilians so caught. A baby is crying and all efforts fail to muffle the cries or get the baby to stop. Do you kill the baby to save everyone else? (that's not really the important question). Here's the thing. Women as a group are the most likely to say no. People who have had children are more likely to say no. People, especially men, who have not had children are morel likely to say yes.
I'm sorry that I won't be able to give the sort of answer that you want. I'm not sure what the answer is. I think it's a very complicated question. If you gave me a problem in general relativity and asked me to solve it, I also couldn't give you a definite answer. But that doesn't mean that there isn't an answer.

But I'll try to do a little better. I think that the evolved sense isn't exactly arbitrary in the way that I suggested above. It's very well adapted to making certain moral choices. That doesn't mean it's always right (from my perspective of a semi-absolute morality). But the more we understand about it's evolution, the more that we can see where it should be trusted, and where not.
Similarly, if I want to catch a ball, I can trust my brain to do the intuitive calculus for me, and I don't need to do the calculations by hand. If I tried, I'd be more likely to make mistakes (not to mention much too slowly), and miss the ball. But I also know where my intuitive physics fails, and I can try to use other means in those circumstances.
Our (or at least my) understanding of morality is, I think, still far from advanced, but things like what you show above (that women or people with children are more likely to make a particular choice), are helping to improve that.

Here is the next important question to consider with the first: Don't you bring your perspective and genetic predisposition to bear on the problem? If you knew that there are different parts of the brain that fire (stastically) depending on gender and/or whether a person has a child or not. Does that come to bear on the dilemma?
It does, but the more I understand how my brain works, the more that I can use the parts that are useful in the situations where they are useful, and try to correct for the rest.

So you do believe that morality is a priori? It must be. That is the only way you could come to this conclusion.
Basically, yes. :)
 
Evolution is guided/shaped by the environment.
If there is something in the environment that would favor a genetic tendency towards moral behavior, then there is a connection.
Otherwise, moral behavior is learned, and "acquired characteristics" aren't genetic in nature.. See Lamarck.
 
And the reason that I missed it is because Princess made no such citations; her citations were entirely erroneous and she's making false accusations.
Well, either people were ascribing a normative value to evolution, or their comments on evolution were irrelevant to the question posed, which was "How can you justify your diet?"
 

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