BawoEn, Psychological Theory of Evolution. 261 
scale, but holds that at some point or other it evolves out of 
unconscious or pre-conscious inorganic nature. He says, it is 
true, that what we call consciousness has developed from some- 
thing more simple than consciousness, but of the same order 
of existence—‘‘germinal states’’ of consciousness, as he calls 
them. But this must mean one of two things: either these 
‘‘serminal states’ are forms of consciousness, or they are not. 
There is no realm between the unconscious and the conscious 
answering to ‘‘germinal states.’’ To posit sucha realm and 
call it ‘‘infra-consciousness’’ is simply to create a problem out 
of words. 
The other writers mentioned also hold in one form or an- 
other that consciousness appears at some point subsequent to 
the appearance of life upon the earth, but none of them say 
just where that point is to be found, and they all differ in their 
attribution of consciousness to certain doubtful types. 
ROMANES’ doctrine of the criterion of consciousness, in 
some of his statements, comes back to the criterion of purpos- 
iveness, though he recognizes and attempts to obviate the diffi- 
culties which that theory presents. The positive value of his 
criterion comes out when he states it as the ability to learn by 
experience. Stated in this way, his criterion of consciousness 
asks, ‘‘Does the organism learn to make new adjustments or to 
modify old ones in accordance with the results of its own indi- 
vidual experience ?’’* Purposiveness taken in itself, in other 
words, is not a sufficient criterion of consciousness. It is that 
purposiveness which is shown under conditions of organic ten- 
sion that is conscious, purposiveness which involves the ability 
to choose this rather than that method of adaptation or adjust- 
ment. Purposiveness means simply adaptation of means to ends. 
Consciousness means the ability to vary the use of means in the at- 
tainment of an end. The former may be quite automatic. The 
latter alone must be conscious. Romanes, of all these writers, 
comes the nearest to an adequate statement of the condition 
and criterion of consciousness. 
1 Animal Intelligence, p. 4. 
