Phil Johnson-Laird is emeritus Stuart professor of psychology at Princeton University after earlier academic positions in England. Ruth Byrne and his collaboration began in 1986 at the MRC's psychological unit in Cambridge and it led to Deduction. Phil continues to do research in collaborations with Ruth and other friends into reasoning, creativity, emotions, and psychological illnesses. He has published over a dozen books and several hundred papers. This research has been recognized in elections to learned societies in Britain (FRS, FBA) and America (NAS, APS), in honorary degrees, and in the award of the Fyssen prize for studies in rationality.

Ruth Byrne is the Professor of Cognitive Science at Trinity College Dublin. Her research on reasoning and imaginative thought has been published in over 150 papers and her former books include The Rational Imagination (2005). She is a member of the Royal Irish Academy and a Fellow of the Cognitive Science Society. She has been awarded the Royal Irish Academy's Gold Medal, and the European Society for Cognitive Psychology's Broadbent Prize.