THE PSYCHOLOGICAL THEORY .OF ORGANIC 
EVOLUTION." 
By H. Heatu Bawpen, Ph.D. 
This paper consists of three parts. The first part isa 
somewhat metaphysical introduction which, if not clear, at least 
possesses the merit of being brief. It sets forth certain impli- 
cations of what is here called the psychological theory of organic 
evolution. The remainder of the paper is an application of 
this point of view to the evolution of consciousness in a con- 
sideration, first, of the evolutionary conditions of the emer- 
gence of consciousness, and, second, of the stages in that 
evolution. 
The aim is to understand the process by which conscious- 
ness has been built up. In man, the highest representative in 
general intelligence of all the mammals, we find a relatively 
continuous and comparatively well-organized consciousness. 
Human consciousness is not absolutely continuous.’ It lapses, 
for example, in dreamless sleep. Nor has human conscious- 
ness reached the highest degree of organization possible, as the 
imperfections of language alone bear witness. But compared 
with what we know of the consciousness of the lower animals, 
the mammals, and especially man, possess a continuity and 
organization of consciousness not found in the lower forms. 
Assuming that this complex consciousness, like everything else 
organic, has resulted from a process of gradual growth, the 
present inquiry is into some of the conditions and stages of 
that growth. 
1 A paper read before the Baconian Club of The State University of Iowa, 
March 15, 1901. 
? Though it is self-healing over the gaps. 
