Those moral thinkers who expound an ethical (or meta-ethical) theory in which it is necessary to prefer one moral perspective over another are what I am calling here Law ethicists. The strongest example of a contemporary figure in this space is Derek Parfit, who vigorously defends a kind of Kantian consequentialism based on his strong beliefs about reason. Parfit recognises that ethics changes over time, and can indeed be improved, but believes that there can be (indeed, must be) a true account of moral judgements. This is the hallmark of Law ethics.
Conversely, what I am calling here Chaos ethicists either do not recognise, deploy, or prefer a single system of moral thought (e.g. Nietzsche) or propose a form of ethics which is inherently non-systematic in nature (e.g. Kierkegaard). The subtle difference between these two positions rests between a denial of any kind of absolute ethics, and the resistance of the negative consequences of faith in an absolute ethics, both of which can be found in the moral philosophy of Alain Badiou, who typifies the contemporary exponent of Chaos ethics with his ‘ethic of truths’.
I actively encourage discussion and assistance in my attempt to crudely divide this list of historical figures from moral thought into these two caricatural camps. A question that divides the two in each case could be imagined to be: “Is there in principle one correct answer to every moral question?" or, equivalently, “Can all moral questions be resolved by appealing to reason?”
Muhammad? (except on Sufi accounts)
Paul of Tarsus
Judith Jarvis Thomson
Siddhārtha Gautama Buddha
Jesus of Nazareth
All help and discussion welcome!