WAYS OF NATURE 
the water was rough; but I could not look upon it 
as an act of conscious or individual intelligence on 
the part of the bivalve. It was as much an act of the 
general intelligence to which I refer as was its hinge 
or its form. But when the sailor anchors his ship, 
that is another matter. He thinks about it, he rea- 
sons from cause to effect, he sees the storm coming, 
he has a fund of experience, and his act is a special 
individual act. 
The muskrat builds its house instinctively, and 
all muskrats build alike. Man builds his house 
from reason and forethought. Savages build as 
nearly alike as the animals, but civilized man shows 
an endless variety. The higher the intelligence, the 
greater the diversity. 
The sitting bird that is so solicitous to keep its 
eggs warm, or to feed and defend its young, prob- 
ably shows no more independent and individual 
intelligence than the plant that strives so hard to ma- 
ture and scatter its seed. A plant will grow toward 
the light; a tree will try to get from under another 
tree that overshadows it; a willow will run its roots 
toward the water: but these acts are the results of 
external stimuli alone. 
When I go to pass the winter in a warmer climate, 
the act is the result of calculation and of weighing 
pros and cons. I can go, or I can refrain from go- 
ing. Not so with the migrating birds. Nature plans 
and thinks for them; it is not an individual act on 
130 
