177 
the harmony, however, being only kept up so long as we look at 
things in the aggregate. We cannot—in order to explain the 
differences of things—separate one thing from another in the 
complicated network in which they are all involved. We cannot 
so distinguish the multiplied agencies at work to bring about all 
we see, as to be able to give a reason for everything. We see, so 
far as relates to man, the whole tending for good; we see a 
general advancement in that direction ; but when we restrict our 
view to particulars, we are soon lost in a maze of difficulties and 
seeming contradictions. 
Any attempt to explain animal structures must be based upon 
a correct ascertainment, in the first instance, of all the facts 
bearing upon the question. It is the business of science to 
collect these facts,* in connection with the circumstances under 
which they occur. When got together science may draw certain 
inferences from them, but it can seldom prove its deductions to 
be right. We see clearly that some structures are admirably 
adapted for certain purposes, as that of the human hand, for 
instance—the subject of one of the volumes of the Bridgwater 
Treatises—but we see other structures, of which we cannot say 
whether they are of any use or not; and others again of which 
we can say positively that they are of no use at all. 
The fact is that circumstances are always changing, often 
involving a corresponding change in the structures of animals, 
without reference to any particular purpose. An animal thus 
affected hy its environment is compelled to adapt itself to its 
altered circumstances. Or rather we should say nature alone, 
without any thought or intention on the part of the animal, 
‘ 
tet 
” . “The naturalist should not sutfer the search or the discovery of a 
Pinal Cause of nature’s works to make him under-value or neglect the 
Studious indagation of their efficient causes.”—Disquisition on Final 
Causes, by the Hon. Robert Boyle, p. 229. This little volume, 
published in 1688, is probably not much known. 
