To the Editor: I thank Dr. Gossart and Dr. Lembke for their comments on my recent editorial. Dr. Gossart and I agree that Cartesian dualism is no longer useful in psychiatric discourse. Nevertheless, the decline and fall of Cartesian thinking does not mean that we should dispense with the domains of "mind" and "brain" in our language. The brain is a third-person phenomenon that can be directly observed and is therefore perception based. The mind involves the complexities of subjectivity, meaning, and consciousness and is a first-person phenomenon that can never be directly observed since it is introspection based. In Descartes’s model, the mind was an entity distinct from the body. It merely intersected the body at the pineal gland. My frame of reference in my editorial was quite different. Indeed, my whole argument was that because mind is the activity of the brain, the two are inextricably tied to one another. Even more important, both domains are relevant to the practice of psychiatry. If we do not keep both in our awareness, we are vulnerable to the perils of reductionism.