Resolved: That ethical non-naturalism is a superior ethical theory to ethical naturalism.

Premise 1: Assuming moral realism, moral claims are either reducible or irreducible to non-moral facts.This premise is best explained via analogy. If you go to a library, there will either be book(s) or no book(s). This is not a false dichotomy. It's simply descriptive of the options that we are given. Now with moral claims, they can either be reduced to non-moral facts or not. It's a yes/no question in this case. And so disproving A necessarily implies B since A and B are the only two options and common sense dictates that one must be true. So a refutation of one theory both fulfills a negative burden to refute the opponent's case a positive burden to bring one's own case. Premise 2: Ethical naturalism holds that moral claims are reducible to non-moral facts.Premise 3: Moral claims are not reducible to non-moral facts.This was brought up by Hume in his is-ought problem. There is a gap that still exists between a descriptive claim about the world(abortion is an act of killing) and a prescriptive claim(one should not have an abortion). This is because there is no evaluative premise involved as to the moral status of killing. It is simply pre-supposed. An example would be an argument not to eat spinach. P1: Spinach does not taste good. C1: I should not eat spinach. It lacks a necessary premise to justify the conclusion. If a P2 was added in that said, "I should not eat things that do not taste good." then the conclusion would logically follow. The same goes with justification of a jump between descriptive and prescriptive statements.The way ethical naturalists propose a way around this problem is to add an evaluative premise on what makes things good, which are identified with natural properties(e. g. eating causes pleasure, pleasure is good, people should eat). But ethical naturalists run into another problem in order to avert the is-ought problem. Moore called it the open-question argument and from there, the naturalistic fallacy. The open-question argument states that assigning natural properties to moral concepts inevitably results in another open-question. Take for example the question of whether or not abortion is wrong. An ethical naturalist would try to explain the morality or immorality of abortion with reference to a natural property that it entails. Most of the time it would be in reference to the fact that abortion takes a life and because of this, it is wrong. But this leads us to another question of why taking a life is wrong. We have simply replaced the term abortion with killing. Explaining moral concepts via natural properties is what Moore called the "naturalistic fallacy". Conclusion 1: Moral claims are irreducible to non-moral facts.As was explained before, there are two options. Either moral claims are reducible to moral facts or they are not. Since I have sufficiently shown why when tying to reduce moral claims, one must first come over the is-ought problem and the necessary conditions to move past the is-ought problem make one run into the open-question argument and the naturalistic fallacy, moral claims are thus irreducible to non-moral facts. In order to refute this line of reasoning, my opponent must either show that there is a third option that my reasoning implies that I am not mentioning, show a naturalistic bridge between descriptive and prescriptive statements, or show a way around the open-question argument. I will go more indepth into my points once I see what kind of reasoning my opponent plans to use. But for now I feel I have made a sufficiet first case and I now pass the debate back to my opponent.