Can morality be absolute? Thanks everyone for the replies. It is possible that I am using terms loosely as I have not spent long studying formal philosophy. In order to try to explain myself as clearly as possible, let me give a thought experiment.
Anne and I are the only two remaining humans in the universe. We have a house and enough water but are short of food.
I tell Anne "Let us kill and eat our Dog."
She tells me "no that is immoral, I would rather starve instead"
From what I understand, these are the different ways of analysing that situation.
Case 1
God/Religion decrees that it is right/wrong to kill the dog. As God/religion has an infinitely superior morality to us, it is right/wrong to kill the Dog. Alternatively morality itself comes from God/religion, so we should always follow what God/religion says
If we disagree, we are simply wrong about the matter, due to our ignorance or flaws.
Case 2
There is natural fact of the matter that it is right/wrong to kill the dog, We may not know the answer, but there is an objectively correct answer, whether or not we know it.
Case 3
Each of us has our own morality, and both are right for themselves. So for me it is moral to kill the Dog, and for Anne it is immoral. We are both correct.
Case 4
Morality is whatever consensus can be achieve by the society. We talk between us and decide that it is right/wrong to kill the dog. Whatever we collectively decide is right/wrong, is objectively right/wrong in our society.
Case 5
Morality is derived from higher state objective laws. Such laws include:
-Maximise happiness
-Minimise suffering
-Treat people as an end in themselves and not as the means to your ends.
From those higher state objective laws, we can derive whether it is morally right/wrong to kill the dog. There is an objective fact of the matter based on the above laws, whether we are able to derive it or not.
Case 6
Morality is whatever rules and norms a society implements. Whatever is decided is then factually what was decided.
Each case may have variants, such as asking what a perfectly rational human what they would think, rather than asking a human what they think. Of course this brings up the question of what exactly is a perfectly rational human - does such a person even conceptually exist?
Some of the cases which suggest an objective morality, still leave open how we can know of that objective morality, and how we can be confident of our knowledge is in fact the correct knowledge.
Out of those options I outline above, the concept of morality that currently sits best with me is Case 4. I'm not sure if that would technically be cultural relativism, or not - perhaps someone will elucidate on that.