There is no compelling reason to believe that objective moral facts exist.

Con's Counterarguments Normative Contingency First of all: what I argued "everyone acknowledges" is that "moral facts" are all contingent all the moral frameworks within which such propositions are contextualized. I was simply extending the contingency analysis to the frameworks themselves. Second of all: at the point that he agrees that normative contingency "is a valid argument", I have won the debate. This is because the normative contingency problem directly undermines the possibility of objective morality by challenging the nature of fundamental moral values as being purely arbitrary propositions, and therefore non-binding on an objective level. Even agreeing that my premises are fallacious is irrelevant, as he has conceded the conclusion; however, I will deal with the fallacious premise argument regardless: He doesn't really make a positive argument to address A) which premise he believes is fallacious, or B) how the premise would count as being fallacious. All that really goes on in this paragraph is a big discussion about relative moral values between Hitler and the Jews, and the "problem of 'content'". Overall, it seems to just be another argument which implicitly cedes normative contingency by hinting at meta-ethical relativism. Presupposition Problem I concur that the presupposition problem alone isn't exactly a positive argument against morality. This was not its purpose, however: the presupposition problem was intended to highlight the nature of moral truth as being taken for granted, rather than sufficiently proven. Where the argument gains offense is in combination with the value subjectivity problem, wherein the very possibility of objective values is challenged. In other words, this argument deals with presuppositions about objective values; the next argument deals with whether such claims are even viable. Subjective Value Problem Since Con concedes this argument as well, this is a second impossible obstacle for declaring moral objectivity. If he concedes my argument, which is that values, by nature, cannot be objective, I see no way for him to simultaneously argue that objective values exist without contradicting himself. He attempts to somehow save himself by again appealing to the "problem of content", but this is neither an offensive argument nor seemingly relevant, from what I can tell. It comes down to him arguing "They're just doing what they think is right", which can easily be addressed (and was addressed) by normative contingency. Con's Contentions At this point, Con really has no choice but to concede his contentions, I think. He's actually already conceded contention 2. He's conceded normative contingency and value subjectivity, and never really addressed the question of presupposition. He claims that he has "disproven" my arguments, but, given that he's conceded two and functionally ignored the other, I see no reason to take him at his word. My previous analysis on his contentions can be pulled through. "Content" The argument he is making fails because he offers absolutely no warrant that "killing is wrong". Perhaps it's an opinion that many people share; however, I preempted this argument in Round 1 by demonstrating that collective subjectivity does not pass for objectivity. Based on the lack of warrant for his foundational ethical claim, he doesn't really have any room to argue further. Conclusion Let's take a quick tally: Con has conceded normative contingency and value subjectivity, which, even without considering the presupposition problem, destroy any hope of making claims to moral objectivity. Furthermore, he hasn't really extended his contentions, conceded the second, and will likely have to concede the other two in the final round. He has also dropped his observations. In essence, the case for nihilism remains almost untouched, while a number of holes have sprung up in Con's case. Although there is a final round in this debate, I feel confident that the case for nihilism has, at this point, been irrefutably made.