Our guest on ST is Alexandra Horowitz, author of the bestselling "Inside of a Dog: What Dogs See, Smell, and Know." Horowitz, who teaches psychology, animal behavior, and canine cognition at Barnard College, Columbia University, joins us by phone to talk about her fascinating new volume, which is a collection of essays on how we perceive, discover, and experience the world around us. That book is "On Looking: Eleven Walks with Expert Eyes" --- it's basically a series of walks/conversations that Horowitz shares with experts on an array of subjects, among them an urban sociologist, an illustrator, a geologist, a physician, a sound designer, and the author's own young son. As a reviewer of this engaging and well-written book has noted for Publishers Weekly: "Horowitz...turns neighborhood walks into an exploration of how people interpret the world. Each walk pairs her with a different companion, each experience offering expertise in a wildly different arena, from the fractured geology of Horowitz's native Manhattan to a city block's surprisingly abundant insect life or how blind people experience the world. Some walks playfully dip into academic specialties, as when Dr. Bennett Lorber displays his Sherlock Holmes-like knack for diagnosing passersby, or when urban behaviorist Fred Kent shares his counterintuitive perspective as president of the Project for Public Spaces. Elsewhere, a sound engineer explains the 'auditory restoration' phenomenon, in which the mind fills in unheard sounds, while a typographer examines fonts and lettering on signs and buildings, going so far as to distinguish between different forms of the letter 'Q.' Even when Horowitz leaves her home turf to venture to Philadelphia and to Springfield, Mass., or consults such dubious 'experts' as her dog, Finnegan, and toddler son, her writing remains insightful. The quirks in how each individual processes the same picture provide readers with their own eyes refreshed, ready to take a good look around them."