Daniel Kelly's "Yuck!: The Nature and Moral Significance of Disgust"

Daniel Kelly is an assistant professor in the philosophy department at Purdue University. His research interests are at the intersection of the philosophy of mind, cognitive science and moral theory. In addition to his work on disgust he has published papers on moral judgment, social norms, racial cognition, and cross-cultural diversity.

He applied the “Page 99 Test” to his new book, Yuck!: The Nature and Moral Significance of Disgust, and reported the following:

It isn’t news that philosophy can get pretty abstract and confusing. One way to temper this is to follow the Aristotelian advice to “tell 'em what you're gonna tell 'em; tell 'em; then tell 'em what you told 'em.” Another is to provide pictures. Readers turning to page 99 of Yuck! The Nature and Moral Significance of Disgust will see both strategies in action.

First to catch the eye will be the picture, a psychological model of humans’ disgust system. This is pretty representative of what I’m up to in the book – I trot it out at the end of chapters, incorporating insights worked through within. I needed a way to gather together and represent what was known about the emotion, and show how more specific ideas fit into the bigger picture. The first chapter gets the model up and running; it gathers all kinds of recent findings about disgust, and walks through how the pieces of this model capture and explain the broad themes of that work. It might be surprising that there is a lot of research on disgust, but it turns out that the emotion provides an intriguing window into human nature: only humans have it (why?), it’s shaped by both nature and nurture (how so?), it’s been shown to inform morality in a number of ways (what ways?), leading some ethicists to imbue the emotion with a kind of moral authority (are they right to do this?) I try to answer these questions throughout the book.

The text of page 99 – a little jargony without context – is me tellin’em what I told’em in more detail in the body of the chapter. Its main claim is about how the emotion is influenced by both nature and nature:

“disgust’s sentimental signaling system is a crucial part of disgust’s acquisition system.”

People instinctively signal to each other when they are disgusted by something. The propensity to make that grossed out facial expression (called the gape face) is largely innate, as is the capacity to recognize that another person is disgusted when she is making it (nature). But there is also variation in what different people and different cultures find disgusting; that not everything that triggers disgust is innate points to a role for learning as well (nurture). Page 99 is the summation of my case that it’s the innate psychological machinery underlying expression and recognition of disgust that allows the social learning of different disgust elicitors.

Learn more about Yuck!: The Nature and Moral Significance of Disgust at the MIT Press website.

--Marshal Zeringue