Robert Arp, PhD, is the author or editor of more than three dozen books and close to 100 articles in philosophy and other areas of the humanities. He works for the United States Department of Defense as an analyst by day, while teaching philosophy and humanities courses to graduate students and undergraduate students in the evening and online. He lives with his wife and two children outside of Kansas City, Missouri.

Martin Cohen is an author, editor and educationalist who has written many books in philosophy and social science including the bestsellers, 101 Philosophy Problems (Routledge) and Wittgenstein's Beetle (Blackwell), both widely translated, as well as two reference works for the Dummies series. He works partly in the UK and in France where he lives with his wife, one young philosopher and a cat. His latest book is I Think Therefore I Eat (Turner, 2018).