Not everyone will be convinced by Timothy Williamson’s assertion that philosophy is a science or that “thought experiments” are analogous to lab work. However, one doesn’t have to agree with all points in Doing Philosophy to enjoy the author’s unusually clear exposition on philosophical methods—doing so without trying to bring the subject down to some imagined “street level.” The Oxford University professor is especially illuminating in his remarks on being skeptical of skepticism. After all, it’s been the project of tobacco giants, climate change deniers and militant postmodernists to raise doubt about the certainty of any knowledge. As Williamson puts it: “A life that never engages with philosophical theories is not fully reflective.” Of course, he would admit that he wasn’t first to think of that axiom.