How can something as simple as a smile be so deceptively complex? That’s the mystery and magic explored in Smile: The Astonishing Powers of a Simple Act, which explores the sensation and science of the smile. From the broad beaming grin of a toddler to the oily smirk of a used car salesman, smiles convey an enormous range of emotions. Grins also have radically varied meanings in different cultures, as the author learned during his many worldwide trips to explore the complicated, but ubiquitous, act of smiling.