RBG said:
You can't just say "naturalistic fallacy" and expect that to be a valid counterargument to any point. You need to explain why the fallacy applies to the situation in order for your calling out of the "naturalistic fallacy" to be valid. Just because it looks like a fallacy doesn't mean it is actually a fallacy.
Also, nice to see that you didn't read the criticism section of the article to see why it (arguably) isn't a true fallacy.
Deck Knight's "argument" is:
we, at some point, derived significant benefits from eating meat. Therefore, it is morally justified to eat meat. This is just an offshoot of the generic
we evolved in order to eat meat, I mean just look at our teeth and digestive systems and stuff argument that every run-of-the-mill "low-brow but strangely educated" 17-year-old posts in a Facebook comments section.
I guess you want me to give some sort of in-depth explanation as to why it makes no sense to arbitrarily assign moral value judgments to
biology, but I struggle to see the merit. Just because an argument seems to make intuitive sense doesn't mean that it is comprised of anything more than convenient (but ultimately meaningless) pattern identification: "look at these teeth that can cut through animal flesh! Oh look, what a surprise, that's exactly what our biological ancestors used them for! It must follow that that is precisely the
correct thing for us to have done. Morally! And well hey, what's stopping us from saying that it's the correct thing for us to
continue to do! You know-- morally!!" As far as I'm concerned, the fact that this is clearly emptyheaded thinking isn't something that needs to be "explained" per se; merely "pointed out."
It needs to be "pointed out" that Deck Knight's argument strictly doesn't follow any line of logic. It needs to be "pointed out" that Deck Knight's argument is "convincing" in the same way that many religious debaters try to convince people that God exists, or that scam artists and psychics manage to fool so many people-- by using irrelevant sensationalism (check), theatrics (check), and appeals to very specific sets of "facts" which, while completely devoid of any logical consistency, "just seem too perfect" to our emotionally-vulnerable, reaffirmation-seeking brains. Biologically, we are capable of killing and eating animals for nutritional (and perhaps cognitive) benefit. This, intuitively, seems like a nice, innocent template from which we can pattern our future behavior. But what about the other things we are "biologically capable of?" My understanding is that rape was relatively prevalent in our biological ancestors (it certainly is in animals), and we can imagine many potential "evolutionary benefits" of such behavior. If this is the case, I think Deck Knight has a few posts to revise in the recent "male rape" thread-- after all, he has shown us that arbitrary moral value judgments can be assigned to picked-and-chosen bits of biological "history" with impunity (whoops, I think I just "explained" by accident).
But of course, he won't actually do that. That would be crazy and irresponsible, not because there is any appreciable argumentative difference between the two scenarios, but because meat-eating happens to be popular at the moment, and it is therefore easy to curry emotional favor with those desperate to settle their cognitive dissonance by drawing irrelevant patterns in a confident tone. So he ignores the inconsistencies and lets you do the rest of the work, because, appropriately, you're kind of biologically wired to do so. I think there might be some irony in there somewhere!