698 The American Naturalist. $ [September, 
zeal, so I beg him to permit me to point out the more freely 
the objections to his main assumption. 
In Professor Baldwin’s latest paper, above referred to, he has 
“ gathered into one sketch ” an outline of his theory. In this 
pamphlet, as in all else that he has written on this subject, we 
are presented with a vast pyramid standing on its apex. We 
are told how he conceives Evolution to work under his assump- 
tion, and gradually his story narrows toward an explicit state- 
ment of what this assumption is. Unfortunately, however, the 
vast superstructure closes in to a cloud of mist, and does so, 
alas, not only before he has made clear in exact detail what 
his assumption is, but even before making understood how the 
things he vaguely suggests could ever clearly be conceived to 
be possible. 
The gist of Mr. Baldwin’s notion is that Pleasure-Pain is a 
psychic “ factor ” that crucially determines Evolution. Pleas- 
ure results from beneficial stimulus. It causes, in turn, “ exces- 
sive” neural discharge. Neural discharge causes “expansion.” 
Expansion brings the creature into continued subservience to 
the beneficial stimulus. Excessive neural discharge makes the 
paths of actual discharge more pervious to the continued 
stimulus and to subsequent discharges from the same source. 
Thusa“ Circular Reaction ” becomes fixed which, because it is 
beneficial, conduces to the preservation at once of the peculiar 
habit and variation in the organisms so developed, and also of 
the creature in which it is developed. The antithesis of all 
this happens with pain. 
Now for the difficulties ; and to bring them out let us imagine 
an unorganized creature before us—say an ameba. Our 
problem is to find how it becomes organized. Let us imagine 
it attacked by any given stimulus at some point of its periph- 
ery. Mr. Baldwin tell us that if this stimulus is beneficial it 
will give pleasure, and the pleasure will cause “excess move- 
ments.” Mr. Baldwin does not pretend that these are yet or- 
ganized movements. To do so would be to beg his whole ques- 
tion. Yet he claims that this unorganized movement would 
complete his “ Circular Reaction ” with the beneficial stimulus 
and perpetuate the beneficient work. But how can we conceive 
