MacIntyre points out in this chapter that moral arguments are basically interminable. His point is similar to what Rorty says about debates in general, although unlike the liberal/postmodernist Rorty, MacIntyre does not believec that this relativism is an objective feature of the world, and he does not see it as a desirable state of political affairs. He points out that in moral debates there is no transcendent or objective criteria by which the two parties can come to an agreement. Instead, it is basically just a shouting match. MacIntyre refers to this state of affairs as 'emotivism.' Moral propositions are understood in society, not as referring to objective features of the world, but as mere expressions of emotion. For someone to say that something is "good" is merely to express their personal preference for something. For someone to say something is "bad" or "evil" is merely for them to express their personal distaste for something. The aim in political debates in the modern world among liberals is not to demonstrate or prove that a specific moral proposition reflects an objective state of affairs in the world; instead, it is to attempt to dominate and coerce our opponents into agreeing with us.
The problem with the liberal political order of the postmodern West is that, because of the pretense to 'neutrality' and tolerance, debates concerning morality which take place within them entail debates between totally incompatible worldviews. MacIntyre adopts the language of Thomas Kuhn and refers to these worldviews as 'incommensurable.' Both worldviews have fundamentally different and incommensurable criteria for determining what is right or wrong. The Christian thinks that abortion is objectively wrong because we believe that life begins at conception. We believe that life begins at conception because it can be deduced by good and necessary consequence from the Bible. We hold the Bible as authoritative on this and other issues because we believe it to be the infallible word of a transcendent God. The liberal rejects all of these assumptions. They believe that reason is immanent to mankind, rather than dependent on a transcendent standard, and accordingly, they may determine that life does not begin at conception, and even if one might concede that it did, they prioritize the right of the mother over the life of the fetus/infant. Obviously, the metaphysical indicates upon which moral imperatives are grounded are totally incommensurable, and thus, political discussions on these issues devolve into pointless shouting matches.
Thus, there are two problems with the liberal political order of the postmodern world:
1) The liberal and the postmodernist have no objective crieteria upon which to ground moral propositions. Even by their own standard, moral propositions are mere expressions of personal preference or emotion. If somebody else disagrees with them, the postmodernist has no objective criteria by which a disagreement can be rationally mediated. For the liberal to insist that another person adopt their moral presuppositions is merely for them to attempt to emotionally coerce someone into submitting to their beliefs. It is hardly compatible with the notion of 'tolerance' purportedly advocated by the liberal. Concealed beneath the veneer of neutrality and tolerance is a worldview which necessitates a Hobbesian war of all against all, or perhaps a Nietzschean storm of conflicting wills-to-power, that is devoid of any objective or transcendent criteria by which moral debates may be rationally mediated. Of course, the liberal only appeals to relativism as an argument against those positions with which he disagrees. He does not sincerely feel that way about his or her own beliefs, and insists on their rectitude as though they were objective features about the world. The inevitable logical upshot is clear: One cannot be a Nietzschean about the metaphysical indicatives from which one's political ethics flow and at the same time hope to retain the imperatives of a truly 'tolerant' social order. In fact, the notion of a truly tolerant political order is an unthinkable thought, and a contradiction in terms. One always holds to a specific worldview about the world, which entails a de facto exclusion of worldviews, with whose metaphysical presuppositions one holds as incompatible with one's own, and this will likewise entail an incommensurability in the moral propositions which necessarily flow from those metaphysical indicatives. Politics, as Carl Schmitt argued, is essentially war.
2) Even where a person rejects the notion that a moral proposition is an expression of mere personal preference, and is mediated rationally by a transcendent, objective criteria, there is no way of mediating between the worldview-presuppositions of such a person and a liberal or a postmodernist. Since both implicitly hold to incommensurable worldviews, neither can ever come to an agreement on very important issues. Thus, the only option is that political discussions will devolve into shouting matches during which the parties can never come to any agreement.
MacIntyre then elaborates on a point made earlier according to which our moral language is an incoherent hodge-podge of incompatible worldviews and philosophies:
"It is easy to see that the different conceptually incommensurable premises of the rival arguments deployed in these debates have a wide variety of historical orgiins. The concept of justice in the first argument has its roots in Aristotle's accounts of virtues; the second argument's genealogy runs through Bismarch and Clausewitz to Machiavelli; the conceptof liberation in the third argument has shallow roots in Marx, deeper roots in Fichte, in the second debate, a concept of rights which has Lockean antecedents is matched against a view of universalibility which is recognizably Kantian and an appeal to the moral law which is Thomist. In the third debate an argument which owes debts to T.H. Green and to Rousseau competes with one which has Adam Smith as a grandfather. This catalogue of great names is suggestive; but it may be misleading in two ways. The citing of individual names may lead us to underestimate the complexity of the history and ancestry of such argumentes; and it may lead us to look for that history and that ancestry only in the writings of philosophers and theorists intead of those intricate bodies of theory and practice which constitute human cultures, the beliefs of which are articulated by philosophers and theorists only in a partial and selective manner. but the catalogue of names does suggest how wide and heterogeneous the variety of moral sources is from which we have inherited. The surface rhetoric of our culture is apt to speak complacently of moral pluralism in this connection, but the notion of pluralism is too imprecise. For it may eqeually well apply to an ordered dialogue of intersecting viewpoints and to an unharmonious melange of ill-assorted fragments. The suspicion...that it is the latter with which we have to deal is heightened when we recognize that all those various concepts which inform our moral discourse were originally at home in larger totalitites of theory and practice in which they enjoyed a role and function supplied by contexts of which they have now been deprived"(MacIntyre, 2011, pp. 11-12).
MacIntyre likewise insists on the importance of avoiding the tendency to treat philosophers as though they all held the same worlview-presuppositions. They did not. They occupied radically different social, cultural and historical contexts, and their presuppositions about the nature of reality were oftentimes radically different from, and at odds with, each other (MacIntyre, 2011, p. 13).
MacIntyre, Alasdair (2011). After Virtue. London, UK, New York, NY. Bloomsbury Publishing, Plc.