We have intimated that primitive consciousness may occur in a sub-conscious way in the highest organisms. But can this sub-consciousness ever be more than mere survival in its nature? or may it play essential part as basis of higher manifestations? If the integration of mentality is like other integration,—_e.g._ material which is based on molecular and atomic activity—it will be bound up in the activity of psychic units, which can be none other than sub-consciousness. That is, any common or general consciousness when looked at from below, and analytically is the dynamic organic whole of elements; it is a product of activities which are on another plane from itself. Roughly illustrated, I may say that my finger feels pain before I do. We conceive that at a certain intensity a sub-consciousness tends to rouse a general consciousness, and for a time maintain it; and losing intensity, the general consciousness disappears leaving only the sub-consciousness, which may long outlast the general form. Sub-consciousness, whether as survival or basal, is put beyond our direct observation, but it remains a necessary biological and psychological hypothesis. Here is exemplified for psychosis that law of the aggregation of units in hierarchical order, that wheel within wheel structure of the universe, upon which I have touched in _Mind_, ix. pp. 272-3. CHAPTER III _THEORIES OF PLEASURE-PAIN_ The bearing of our studies on a theory of the conditions of pleasure-pain is obvious. If we consider pure feeling as the primary, fundamental, and conditioning mentality, it stands before all other mentality, and cannot be interpreted as conditioned. Pain as _primum mobile_ is not intrinsically dependent on any other psychosis. Hence we run counter to the Herbartian School, which maintains that psychism exists from the first for itself as intellectual ideational activity, and that pleasure-pain is but reflex of the efficiency and ease, or the inefficiency and difficulty of this activity. The checking of the current of ideas may give a pain, but our exposition has been that pain arose before ideas or presentations of any kind, and long before any interference could be felt as pain.