MOST OF US read or look at art in order to feel something - to experience sensations perhaps unavailable to us in everyday waking life. But it's not just our feelings. Encountering the visions of the past, we also begin to acquire a sense of how people used to feel as well.

These are the issues that animate the work of the literary critic and poet Sianne Ngai. In her new book, Our Aesthetic Categories: Zany, Cute, Interesting ($39.95, Harvard University Press), she considers how those feelings help us form judgments about the aesthetic world, how we know to describe something as "interesting" or adorable.

At first, talking about aesthetic experiences can seem dreary and specialized. But these conversations are always about more than describing pretty or pleasurable things. For instance, what is the difference between beauty and the sublime? The two categories are suggestive of radically different ways of understanding the world, and the question - one wrestled with by figures like Edmund Burke and Immanuel Kant - contains the anxieties of its time. Beauty is recognition, mastery, a scale that we can comprehend; the sublime remains mysterious, metaphysical. To speak of beauty and the sublime, then, is to have a conversation on rational judgment and faith.

Our Aesthetic Categories, however, argues on behalf of aesthetic experiences that aren't quite so awe-inspiring or rare. Sitting before your computers or walking the streets of your town, you don't encounter beautiful things as frequently as you do interesting, momentarily arresting ones - and as for the sublime, when was the last time you experienced catharsis? Instead, Ngai considers our "minor" aesthetic experiences, the ones that make up our day. The zany, cute and interesting won't stir us to tears or action or a belief in the creator. Rather, these are dashed-off assessments that feel like second nature, given the speed at which things circulate. But these are judgments as rich for unpacking as the beautiful or the sublime.

In Our Aesthetic Categories, Ngai explores these seemingly simple judgments and finds a great deal hidden within.