Most of us grew up with the attitude of a fatalistic intellectual hopelessness. How could we ever be clear on the relation of mind and body? How could mind and soul ever arise out of matter? How can we harmonize strict science with what we try to do in our treatment of patients? How can we, with our mechanistic science, speak of effort, and of will to do better? How can we meet the invectives against the facts of matter on the part of the opposing idealistic philosophies and their uncritical exploitations in "New Thought"--_i.e._, really the revival of archaic thought? It is not merely medical usefulness that forced these broad issues on many a thinking physician, but having to face the facts all the time in dealing with a living human world. The psychopathologist had to learn to do more than the so-called "elementalist" who always goes back to the elements and smallest units and then is apt to shirk the responsibility of making an attempt to solve the concrete problems of greater complexity. The psychiatrist has to study individuals and groups as wholes, as complex units, as the "you" or "he" or "she" or "they" we have to work with. We recognize that throughout nature we have to face the general principle of unit-formation, and the fact that the new units need not be like a mere sum of the component parts but can be an actually new entity not wholly predictable from the component parts and known only through actual experience with the specific product. Hydrogen and oxygen, it is true, can form simple mixtures, but when they make an actual chemical integration we get a new specific type of substance, water, behaving and dividing according to its own laws and properties in a way not wholly predictable from just what we know of hydrogen and oxygen as such. Analogy prompts us to see in plants and animals products of physics and chemistry and organization, although the peculiarity of the product makes us recognize certain specificities of life not contained in the theory of mere physics and chemistry. All the facts of experience prompt us to see in mentation a biological function, and we are no longer surprised to find this product of integration so different from the nature and functions of all the component parts. All the apparent discontinuities in the intrinsic harmony of facts, on the one hand, and the apparent impossibility of accounting for new features and peculiarities of the new units, are shown to be a general feature of nature and of facts: integration is not mere summation, but a creation of ever-new types and units, with superficial discontinuities and with their own new denominators of special peculiarities; hence there is no reason to think of an insurmountable and unique feature in the origin of life, nor even of mentally integrated life; no need of special mystical sparks of life, of a mysterious spirit, etc.; but--and this is the important point--also no need of denying the existence of all the