Below are some comments (names removed) by atheists I have conversed with online at different times and places. I will give their unedited comments so you can see for yourself how these folks think and, most importantly, the logical conclusions to which their worldview takes them.
we are getting to the reality of ethics/morals… RELATIVITY. Something that is bad or ‘evil’ for one being, can be good for another. “Who determines what is evil?” Beings themselves ... My point is that we are talking about choice. Evil doesn’t exist in and of itself. It is not some cloud-like gas floating out in the universe. Evil is determined by the individual being. What hurts mankind must be 'evil,' in terms of mankind ...First, "Relativity" is a physics term referring to Einstein’s General or Special theories. "Relativism" is quite a different thing. I don’t say this to be condescending but many people believe these are synonymous and that we are therefore free to say "everything’s relative!" Nothing could be further from the truth.The scientific concept of light’s velocity being constant regardless of the frame of reference from which it is measured has no similarity to the philosophical claim made here: That moral questions are only decided by "being’s themselves." That claim is a relativistic claim and all claims to relativism are self-defeating and incoherent. In saying this we would have no way to differentiate the morality of another person’s actions. We would have no right to judge Hitler's actions as being "wrong" or, as this commenter claimed prior to this, no framework by which she could label God as a "malevolent monster." Both God and Hitler just do what they do because, "Something that is bad or 'evil' for one being, can be good for another." The commenter wants to define his own morality and is quite adamant about the fact that is his prerogative to do so ...
Naturally, I think you’re wrong. You keep trying to establish “oughtness” as the basis of all things, as though the universe could not operate without it…and yet it does, every single day. “Should” is an opinion; “ought to” is an opinion. The only thing that is objective are the facts; everything else is an opinion. Morality is a personal choice; whatever source we take it from is no more objective than any person or circumstance we apply it to.
I didn’t say morals don’t exist. I said they are relative. I can make any moral judgment I please. There is no absolute moral standard for relative beings. As I said earlier, I have moral/ethical beliefs.
I don’t believe in objective “morality,” so I don’t adhere to the “shoulda woulda coulda” rationale. However, if I were to qualify a set of guidelines by which I prefer to adhere as “morality,” then I would say that I construct those guidelines based on what is most effective towards reaching my personal goals, which primarily consists of the happiness of myself and others.
These are from different folks but carry the same message -- one that deserves comment. The view they hold is completely self-defeating in this sense: They claim that morality and truth are relative to the individual or group who chooses to adhere to them. That being the case, their truth and morality would hold no more weight than my truth and morality. Neither of us could claim to be right or wrong under their standard of establishing truth or morality. Yet, in the same breath, they say things like "I think you are wrong."
Now, there is nothing wrong (no pun intended) with saying that on my view. But on their view it is completely incoherent because on their view no one can claim to know whether anyone's claim to know the truth is valid. Their statements about these things defy the very claims of their own worldview!
I try to approach this problem by asking a simple question: "Do you think I am wrong to say relativism is false?" If they say I am wrong to say that, they are admitting to an absolute truth claim about the proposition. If they say I am not wrong, they are admitting that relativism is false. Either way, relativism ends up being false.
And this is why it is so frustrating. The reasoning they have to resort to defend themselves is maddeningly circular. You can go on and on like this until you are ready to scream. But scream you cannot. If you get angry, you lose. If you get them angry, you lose. Unfortunately, I have lost far too often in both ways.