hile traditional theories regard mind as an intruder from without into the natural development, or evolution, of organic structures, or else in the interest of natural continuity feel compelled to deny that mental behavior has any differential features, the theory that organic responses have mental quality in the degree in which they deal with the uncertain recognizes both continuity and difference. It can, in principle if not as yet in detail, give agenetic account of the development of mental and intellectual processes. There is neither asudden jump from the merely organic to the intellectual, nor is there complete assimilation of the latter to primitive modes of the former.