The Logic of Mortality is based on the Gifford Lectures delivered by Anthony Flew at the University of St Andrews in the academic year 1986–87. Flew approaches natural theology through an argument over the possibility of the existence of the human soul as a substance distinct and separable from the human body. Following a lengthy examination of the historical context of the mind-body problem, Flew concludes that the idea of a personhood which resides outside of a corporeal form is substantiated neither by logic nor by science.