40 
WILLIAM KEITH BROOKS 
pleasure, on the nature and intellectual value of what we can learn. 
His thoughts in this field of the principles of science were event- 
ually embodied in his lectures on the ^'Foundations of Zoology" 
(1899). This remarkable book ''belongs to literature, as well as 
to science. It belongs to philosophy as much as to either, for it is 
full of that fundamental wisdom about realities which alone is 
worthy of the name of philosophy. "20 
Brooks was distinctly the philosophic type of naturalist. He 
was fully informed, critical, and constructive in special fields, 
but always aware that such fields were merely parts of a larger 
whole. Thus through the bent of his mind Brooks, the keen- 
sighted pioneer, and influential biologist, was also interested in 
and in thorough sympathy with life and living in all aspects, past, 
present and future, intellectual, emotional, and religious. Per- 
haps for that reason, too, he was a great teacher and inspirer 
of men. 
The "Foundations" is essentially a discussion of the nature 
of scientific knowledge. It is the wise talk of an experienced, 
reflective naturalist of ripe years addressed primarily to younger 
fellow-workers in the fields of science. The argument which m^akes 
its way through pages and sometimes whole chapters of illustra- 
tions and digressions, interesting and suggestive in themselves, 
proceeds about as follows : 
Our only knowledge of nature is through experience. Through 
experience we learn that one sort of event follows another, and 
this sequence, which we come to expect, constitutes for us the 
order of nature. Nevertheless there is no reason to believe that 
there is an inherent necessity in this order, for we never perceive 
the presence of any intrinsic causal connection between the pre- 
ceding event (cause) and the succeeding one (effect). 
When our knowledge of any part of nature has so far developed 
that we know the order of events, and so can predict the later 
steps in the series of occurrences, once the earlier have been noted, 
we say that we understand and can mechanically explain that 
particular set of phenomena. At present a gap separates vital 
- 20 President D. S. Jordan. 
