Dr. Kendler avoided the basic problem psychiatry faces, which is, what is a mental state? In so doing, he leaves any potential framework hanging in limbo, maintaining the gulf between the mind and the brain. Dr. Kendler did not mention intentionality, which Brentano noted in 1874 (2) as characterizing "the mental." The concept of intentional causality associated with meaning and belief and the nonintentional associated with chemical and physical law-like relationships can provide an acceptable explanation of mental function. The mind can then be explained in a framework of dynamic intentional and nonintentional causal processes in which top-down and bottom-up causality can explain all mental functions and dysfunctions, from molecular interactions to the higher-level intentional processes that produce consciousness.