ABSTRACT
The nature and function of the human brain are causally connected to other properties in the cluster of properties from which human nature emerges, and it is important to sort out and clarify the nature of those causal connections. It is understandable why some neuroscientists may have made exaggerated claims about the importance of the human brain. Focusing temporarily just on the size of the human brain, given a naturalistic view to which the cluster theory is committed, some plausible explanation must be given for the benefit of its size since that size comes at some significant evolutionary costs. The cluster theory of human nature accounts for the development of the human brain and human reason within a bottom-up, naturalistic framework. The interaction of the normal human brain with its environment is a modern-day interpretation of Kant's dictum that concepts without percepts are empty and percepts without concepts are blind.
