u/genericjobapplicant2

I couldn't think of a better way to make the title a question than the above. My actual question I want to know is just "Why?" but apparently that is too short for a title. Essentially I would like an atheist to explain why these beliefs are not incongruent with each other please. Preferably one who believes them. I'll take any atheist's answer though.

I know not every atheist holds these beliefs, but In my experience talking to atheists it is very common for atheists to hold the beliefs that:

1. morality is subjective and epistemically grounded in the collective moral opinions of people in society,
2. that there are moral truths that apply to people regardless of the beliefs of those people, and
3. that these beliefs do not lead to nihilism being true.

The thing I find odd is that their explanation for why their beliefs do not lead to nihilism are the exact logical structures used to argue for Nihilism on the Stanford Encyclopedia of Philosophy. So if there is an atheist who can explain why this seemingly common set of beliefs is considered to be congruent and logically valid instead of logically incongruent I would appreciate it.

Some reference points for the discussion from the SEP article on moral skepticism:

The definition of Nihilism is described as

"Moral Nihilism = Nothing is morally wrong.

Moral nihilism here is not about what is semantically or metaphysically possible. It is just a substantive, negative, existential claim that there does not exist anything that is morally wrong.Since smart and knowledgable people do take moral nihilism seriously and even argue for it (Mackie 1977, Joyce 2001), moral nihilism cannot be dismissed as readily as Descartes’s deceiving demon."

And the common logical structure I see Atheists use to explain why morality applies to people without nihilism being true is found describing why moral nihilism is true here:

"Moral nihilism by itself is enough to be contrary to common moral beliefs, but it is not explanatory. To make their argument more forceful, therefore, moral skeptics usually add some explanation of why people hold moral beliefs that are false (just as the story of Descartes’s deceiving demon is supposed to explain why we hold false perceptual beliefs). The most popular explanations of our moral beliefs refer to evolutionary and social advantages of holding certain moral beliefs, especially when these moral beliefs are shared throughout society. Shared moral beliefs can facilitate social coordination and cooperation even when they are false (much as a shared non-moral belief that my neighbors will in fact catch and punish me if I ever steal from them will reduce theft and increase trust, even if this belief is false and I actually could get away with stealing).

When bare moral nihilism is supplemented with an explanation of why people would hold common moral beliefs even if they were false, this conjunctive skeptical hypothesis can be called explanatory moral nihilism. Moral skeptics can then argue that explanatory moral nihilism forestalls any refutation. Since moral nihilists question all of our beliefs in moral wrongness, they leave us with no starting points on which to base arguments against them without begging the question at issue. Moreover, their explanations of our moral beliefs predict that we would hold exactly these moral beliefs, so the truth of its predictions can hardly refute explanatory moral nihilism. If this trick works, then it fits right into a skeptical hypothesis argument.

This argument is clearest when it is applied to an example. If nothing is morally wrong, as moral nihilists claim, then it is not morally wrong to torture babies just for fun. So, according to the general standard above, one must be able to rule out moral nihilism in order to be justified in believing that torturing babies just for fun is morally wrong. But one cannot rule out moral nihilism if one would hold the same moral beliefs even if they were false, as claimed by the explanation embedded in explanatory moral nihilism. "