Since his retirement from active teaching in 2010, he remains the senior distinguished research fellow of the Notre Dame Center for Ethics and Culture,[5] where he retains an office.

Although he largely aims to revive an Aristotelian moral philosophy based on the virtues, he claims a "peculiarly modern understanding" of this task.

Following Hegel and Collingwood, he offers a "philosophical history" (as opposed to analytical and phenomenological approaches) in which he concedes from the beginning that "there are no neutral standards available by appeal to which any rational agent whatsoever could determine" the conclusions of moral philosophy.

He revives the tradition of Aristotelian ethics with its teleological account of the good and of moral actions, as fulfilled in the medieval writings of Thomas Aquinas.

More generally, according to MacIntyre, moral disputes always take place within and between rival traditions of thought relying on an inherited store of ideas, presuppositions, types of arguments and shared understandings and approaches.

Even though there is no definitive way for one tradition in moral philosophy to logically refute another, nevertheless opposing views can dispute each other's internal coherence, resolution of imaginative dilemmas and epistemic crises, and achievement of fruitful results.

"[11] However, after reading the works of Thomas Kuhn and Imre Lakatos on philosophy of science and epistemology, MacIntyre was inspired to change the entire direction of his thought, tearing up the manuscript he had been working on and deciding to view the problems of modern moral and political philosophy "not from the standpoint of liberal modernity, but instead from the standpoint of… Aristotelian moral and political practice.

MacIntyre's philippic articulates a politics of self-defence for local communities who aspire to protect their traditional way of life from the corrosive capitalist free market.

[13] MacIntyre's second major work of his mature period takes up the problem of giving an account of philosophical rationality within the context of his notion of "traditions," which had still remained under-theorized in After Virtue.

As its title implies, MacIntyre's aim in this book is to examine three major rival traditions of moral inquiry on the intellectual scene today (encyclopaedic, genealogical and traditional) which each in turn was given defence from a canonical piece published in the late nineteenth century (the Ninth Edition of the Encyclopædia Britannica, Friedrich Nietzsche's Genealogy of Morals and Pope Leo XIII's Aeterni Patris, respectively).

[20] MacIntyre's book ultimately conducts a complex series of both interior and exterior critiques of the encyclopaedic and genealogical positions in an attempt to vindicate philosophical Thomism as the most persuasive form of moral inquiry currently on offer.

His critique in chapter IX of Nietzsche's and Michel Foucault's genealogical mode as implicitly committed to an emancipatory and continuous notion of self which they cannot account for on their own terms has been of particular influence.

For researchers, inquiry at the frontier must advance toward holistic, inter-disciplinary accounts, at once both theoretical and practical, undertaken together by members of communities of practitioners bound together in traditions.

The public hosting of such engagements at suitably-reformed universities, including opportunities for agreement from complementary perspectives and for sharpening differences, would support both adjudication among the mutual claims to rational superiority among rival traditions, and initiation of students into the skill sets required to profitably join and assess such encounters.

MacIntyre is a key figure in the recent surge of interest in virtue ethics, which identifies the central question of morality as having to do with the habits and knowledge concerning how to live a good life.

Before its recent resurgence, virtue ethics in European/American academia had been primarily associated with pre-modern philosophers (e.g. Plato, Aristotle, Thomas Aquinas).

He has been described as a 'revolutionary Aristotelian' because he attempted to combine historical insights from his Marxist past with those of Thomas Aquinas and Aristotle after MacIntyre's conversion to Catholicism.

At the same time, he says that "Marxists have always fallen back into relatively straightforward versions of Kantianism or utilitarianism" (After Virtue, p. 261) and criticizes Marxism as just another form of radical individualism.

"[26] In an interview with Prospect, MacIntyre explains that his conversion to Catholicism occurred in his fifties as a "result of being convinced of Thomism while attempting to disabuse his students of its authenticity.