In the above discussion, I have unavoidably anticipated the second problem: the relation of conceptual thought to perceptual data. A distinct aspect still remains, however. Perception, as well as apriority, is a term harboring a fundamental ambiguity. It may mean (1) a distinct type of activity, predominantly practical in character, though carrying at its heart important cognitive and esthetic qualities; or (2) a distinctively cognitional experience, the function of observation as explicitly logical--a factor in science _qua_ science. In the first sense, as recent functional empiricism (working in harmony with psychology, but not itself peculiarly psychological) has abundantly shown, perception is primarily an act of adjustment of organism and environment, differing from a mere reflex or instinctive adaptation in that, in order to compensate for the failure of the instinctive adjustment, it requires an objective or discriminative presentation of conditions of action: the negative conditions or obstacles, and the positive conditions or means and resources.[38] This, of course, is its cognitive phase. In so far as the material thus presented not only serves as a direct cue to further successful activity (successful in the overcoming of obstacles to the maintenance of the function entered upon) but presents auxiliary collateral objects and qualities that give additional range and depth of meaning to the activity of adjustment, perceiving is esthetic as well as intellectual.[39] Now such perception cannot be made antithetical to thought, for it may itself be surcharged with any amount of imaginatively supplied and reflectively sustained ideal factors--such as are needed to determine and select relevant stimuli and to suggest and develop an appropriate plan and course of behavior. The amount of such saturating intellectual material depends upon the complexity and maturity of the behaving agent. Such perception, moreover, is strictly teleological, since it arises from an experienced need and functions to fulfil the purpose indicated by this need. The cognitional content is, indeed, carried by affectional and intentional contexts.