The Nature of Human Persons

The questions of whether there is a shared nature common to all human beings and, if so, what essential qualities define this nature are among the most widely discussed topics in the history of philosophy and remain the subject of perennial interest and controversy. This book offers a metaphysical investigation of the composition of the human essence—that is, with what is a human being identical or what types of parts are necessary for a human being to exist: an immaterial mind, a physical body, a functioning brain, a soul? It also considers the criterion of identity for a human being across time and change—that is, what is required for a human being to continue existing as a person despite undergoing physical and psychological changes over time? Jason Eberl's investigation presents and defends a theoretical perspective from the thirteenth-century philosopher and theologian Thomas Aquinas. Advancing beyond descriptive historical analysis, this book places Aquinas’s account of human nature into direct comparison with several prominent contemporary theories: substance dualism, emergentism, animalism, constitutionalism, four-dimensionalism, and embodied mind theory. There are practical implications of exploring these theories as they inform various conclusions regarding when human beings first come into existence—at conception, during gestation, or after birth—and how we ought to define death for human beings. Finally, each of these viewpoints offers a distinctive rationale as to whether, and if so how, human beings may survive death. This book’s central argument is that the Thomistic account of human nature includes several desirable features that other theories lack and offers a cohesive portrait of one’s continued existence from conception through life to death and beyond.