> Yes. I don't believe in absolute morals (nor do I believe that many people believing something makes the belief
> true). I suppose absolute morals could exist, but I have thus far seen no convincing evidence to prove it.
I won't try to change your mind, but I will try to state my opinions on these matters.
I believe that absolute morals exist, although I do not believe in them myself, but what I mean by that is that some people believe in absolute morals, so those morals are real and true and absolute as far as they are concerned, even though other people might disagree. This is moral relativism, so I'd figure you might agree with this.
Regarding convincing evidence to prove absolute morals, I think looking for such evidence is missing the point. Science does not have a concept of absolute truth, just experiments and theories and observations. Some things, such as religion and morals, are based on faith, not on experiments or science. When someone has faith in something, they don't need proof. Their beliefs are still real to them, and might make them happy and make them lead healthier more productive lives.
Of course, this is just my opinion, and I'm an agnostic, so take this for what you will.
Finally, regarding the issue of whether most people believing something makes it true, I disagree with you. Most people agreeing on something is what makes it true, by definition. If most people say that apples are red, then apples are red. But what about the colorblind person who sees apples as green? Does that mean that we are all wrong, and he is right, and apples are green after all? No, it means that his vision is broken.
Even in science, when a scientist submits a paper to be published, there is no magic "is this true" test. Rather, a panel of expert reviews vote, and the majority opinion decides what is considered true.
In other words, there is no such thing as absolute truth, there is just observations and opinions. But the way the english language works, when enough people agree that something is true, we say that it is in fact true. This is imprecise and probably repugnant to your ultra-logical mindset, but it is the way the world works.