3 
way. He reflected that Nature never does anything in vain 
(which is the same thing as saying that every structure has 
some final cause); and he was thus taught that the blood 
flows inward to the heart from the parts of the body by the 
veins, and outwards by the arteries. In like manner, the 
doctrine that every structure has certainly some function is the 
very lever of the construction of comparative anatomy. But 
what is this function but the final cause of the structure? ‘To 
discover the function is the main task this science proposes to 
itself. This is the end pursued through all the comparative 
dissections. And when the function, or final cause, is dis- 
covered, the physiologist knows that he has discovered a 
general law, not only of that variety or species, but of all 
species possessing that organ. Cuvier argued: No animal 
devoid of canine teeth will ever be found with its feet armed 
with prehensile claws. Why? Because the function of the 
canine teeth is to masticate living prey; but nature, after 
depriving the mouth of such teeth, and equipping it only with 
graminivorous teeth, will never perpetrate the anomaly of 
arming the feet with claws whose function is to catch living 
prey. Such is the character of the arguments of this great 
science. Deny the doctrine of final cause, and it has no 
basis. 
Indeed, if final causes are discarded, there is no longer any 
basis for any inductive demonstration. The object of this 
process, in every branch of science, is to discover a general 
and permanent law. How do we accomplish this? Let the 
admitted answer be repeated: It is accomplished by dis- 
tinguishing from among the seeming antecedents of a given 
effect, that one which is the “ invariable unconditional ante- 
cedent ”’ (Mill). For the very nature of inductive logic is to 
assure us that when we have truly found this invariable 
unconditional antecedent in some cases, it will infallibly intro- 
duce that effect in all similar cases. This is what is assumed 
as the “natural law.”? But how are we authorised to infer 
this? By our general premise concerning ‘ the uniformity of 
nature.” But the system which discards final cause also 
denies that there is any intuition of a necessary law of cause. 
Now, if there were no other ground for invariable uncon- 
ditional sequence, would an intuitive expectation of the uni- 
versality of any law of cause be better grounded than this 
empirical one? Let this be pondered (our main effort has 
been to show that this expectation is intuitive, and not merely 
empirical, and that for this reason the inductive inference holds 
good). Could the intuitive or @ priori reason consistently 
hold this expectation if it saw in a true cause no efficient 
