The contrast in literary and intellectual style between these two books on the same subject, both by philosophers, could hardly be greater. Here is a typical passage from Daniel Kelly:
Taken together, the emotion of disgust consisted of a rigid, reliable type of motivation and behavior, paired with an open-ended database of elicitors and a flexible acquisition system, enhanced with a sentimental signaling system available for the transmission of cultural information. As new adaptive problems arose, these features, and the mix of rigidity and flexibility they offered, made the disgust system well positioned to be co-opted to new purposes, including purposes that had little or nothing to do with food intake or disease avoidance.
When considered next to each other, (a) the conditions created by the core coevolutionary feedback loop and (b) the nature of the disgust system seem an almost ideal match for each other: the feedback loop generates a variety of new adaptive problems, involving especially social interactions, and the disgust system lends itself to being co-opted to deal with new adaptive problems, especially those involving social interactions.
And here is a typical passage from Colin McGinn:
In the rotting corpse, we see something that once housed a conscious being and no longer does—and it is as if the consciousness still obscurely resides within the body awaiting its final dissolution. The consciously living is still somehow hovering around the organically dead, and the dead impinges on the living: this is a moment of deep metaphysical transition—consciousness turning to mindless, disorganized matter.
Similarly, in feces we can see the death of living things, some of them sentient, which have ended up as food; but as well, we see the life processes of a sentient being at work. The conscious life of the food animal is obscurely present in the feces of the predator—after all, it has been consumed along with the organic tissue—but we can also see the imprint of the conscious life that has done the consuming. Conscious animal digests conscious animal: shit is the visible sign of absorption. The strange vitality of shit, phenomenologically speaking, reflects its embedding in the world of sentience.
Both books address an absorbing and difficult question—the nature, meaning, and value of disgust—that in recent years has generated a large psychological literature. Unlike fear and anger, but like shame and guilt, disgust seems to be an emotion unique to humans, and like language it appears only at a certain stage of human development. It has a great range of objects, and those objects can differ widely among persons and cultures, and over time, though there seem to be some that are universal, such as rotting corpses, suppurating wounds, snot, pus, vomit, excrement, and menstrual blood. Among the objects that vary are species of animal—rats, worms, cockroaches—sexual practices, foods, ethnic groups, and perhaps some moral offenses. Some benighted souls find French …