This runs very counter to what most people believe, but, given atheism, it seems very hard to deny. After all, the materialism which is the basis of nearly all modern atheism denies the reality of any moral truth or value.
Most atheists I know would agree with this, but would emphasize that a person need not believe in moral truth in order to be a nice person. One can claim that morality is simply culturally relative, biologically advantageous, or otherwise subjective, and still be a good person.
This seems true enough, but is a side issue. Whatever I may think of a particular atheist, or even the impact of atheism on social health, the question is over truth. Is it more likely that humans have rights, or that God does not exist? Personally, I think most of us wouldn’t be confident enough of God’s non-existence to accept the idea that people don’t have rights beyond what governments happen to give them. Rather, I think we would say that a government which enslaves its people, or slaughters a racial minority, is in the wrong.
And this is because we have a sense of the moral that is as basic as our sense of the physical. The fact that there is no physical evidence for the moral no more refutes the moral than the lack of moral evidence for the physical refutes the material.
But this does make materialism seem rather arbitrary. It would be rather tidy if we could dismiss all knowledge that isn’t as easily reduced to mathematics as the material. But, setting aside the convenience of it, and the rhetorical value of being “scientific”, I don’t see any reason to think that it is true.
Rejecting a basic fact of human experience as illusory requires a reason that is more palpably true than the experience itself. This could be done in theory, but no one has yet to offer a reason to believe in materialism (or in atheism) that is as obviously true as the fact that it is wrong to torture innocent people.