14 INTERPRETATIONS OF NATURE. 
lection,’ and formulate the laws of biological evolution. 
This generalization, resting as it does upon the truths 
of inductive science, gives to the mind a picture of 
nature’s unity, completeness and design throughout the 
cycle of life. 
Thus has observation caused the belief that the phe- 
nomena of the world are not isolated, but related; and 
that its methods are not capricious, but orderly. 
The idea of ‘‘law’’ has shadowed that of special in- 
terference, and a broader classification deals with rela- 
tions rather than things. 
The relations existing between the worlds of matter 
and of life, which more completely show the unity of 
nature, are not necessarily determined by the physical 
or functional character of the objects related, nor by the 
origin or mode of development of their physical struc- 
tures; but by the finer and deeper relations of adapta- 
tion and adjustment by which the action of physical 
forces upon the organism are necessary for the expres- 
sion and maintenance of vital phenomena. 
The pull of gravity, which defines the orbits of the 
stars and bounds the ocean’s tides, also influences the 
beating heart and the flowing blood. So delicately has 
nature adapted organs and adjusted forces, that the 
pulses of the air break upon the ear as sound, and ethe- 
real tremors are interpreted by the mind as heat, light, 
and actinic force. 
From the sensations resulting from the impressions 
made by external physical forces spring ideas, feeling, 
will; and in the classified relations of such profound 
differences is found the evidence which establishes the 
highest form of nature’s unity. 
Here ends the power of inductive science. It explains 
the phenomena of matter and of life, by classifying facts. 
and by giving a formula for an ‘‘ entire order of phe- 
nomena ;”’’ but it does not explain the verities that 
