In After Virtue, Alasdair MacIntyre tells the story of the companions of Captain Cook who, despite their best efforts, were quite unable to make sense of the morals of the people of Polynesia, which in certain matters were unexpectedly severe: men and women were forbidden to eat together, for example, because this was taboo, though sexual relations between them were quite unregulated. Their attempts to understand the natives' claims that such and such was taboo produced no insight – they could fathom no rationale for the surprising proscriptions and the equally surprising permissions, and they could only judge the system of taboo unintelligible. Anthropologists in our day have concluded that, by the time of Cook, the cultural background in virtue of which the taboo rules had originally been understood and made sense had been quite forgotten, so that what remained seemed to Europeans and, on reflection, to Polynesians too, arbitrary prohibitions. So it was that under the questioning which the outsiders provoked, the whole system, plainly bereft of intelligibility, crumbled in the space of a generation.

For MacIntyre, the story serves as a parable of our present circumstances. As a result of the pressures of the diverse intellectual forces we name the Enlightenment, we have been led to forget the deep accounts of the human good which could render our moral beliefs intelligible.