What Is a Human Being? Human Nature and the Problem of Definition

Few questions look simpler and turn out to be harder than "What is a human being?" We are the ones asking, so we might expect an easy answer. Yet every attempt to fix a single essence that all and only humans share runs into trouble, and this difficulty is the doorway into the whole of IB Philosophy's core theme, Being Human.

Definitions by species, capacity, and function

A first strategy is biological. A human being is a member of the species Homo sapiens: an organism with a particular genome, evolutionary lineage, and anatomy. This is precise, but it may miss what we care about. When we ask what a human being is, we often mean what makes human life valuable or distinctive, not merely which DNA it carries. Biology tells us the boundaries of the species; it does not obviously tell us why a