On Scientific Method. 
[October, 
478 
have succeeded in detecting the connecting-] ink. We have 
made a beginningin the classification of the changes of Nature. 
If the aim of Science be to deteCl identity amid variety, 
it is asked — What means does she employ for accomplishing 
this end ? Observation , Experiment , and Inference. 
From repeated observations we discover an identity ; from 
a number of identities we infer that what is true of one is 
true of another ; from a number of combined inferences we 
draw a wider inference, which again we generalise into what 
is called a law. But before we can establish a law we must 
make use of the process of deduction — if such or such an 
inference be true, then this or that phenomenon must follow. 
Observation or experiment tells us whether the phenomenon 
does occur or not ; if it does, another proof of the correct- 
ness of the law is gained ; if it does not, there is the less 
probability that the so-called law is a true one. Thus it is 
from a series of partial hypotheses which generalise a num- 
ber of faCts that we at last ascend to the hypothesis which 
shall include in its expression all the isolated faCts — that is, 
to a general law. And this method of combined observa- 
tion, experiment, induction, and deduction is the Scientific 
Method. 
There is nothing pecular in this method ; it is but common 
sense reduced to rule. We are continually and uncon- 
sciously guided by the scientific method in our every-day 
conduct. The countryman who, in the morning, assures his 
neighbour that it will rain before midday, bases his assurance 
upon a train of scientific reasoning ; he has repeatedly ob- 
served that certain appearances of sky, a certain direction 
of wind, and rain, are associated together: from these 
observations he has, probably unconsciously, framed the 
hypothesis that the three sets of phenomena are related 
together in such a manner that, given the two first, the third 
is sure to follow ; he has proved the value of his hypothesis 
again and again, by aCting on it, — the only scientific method 
of proving an hypothesis, — and he at last has come to regard 
it as a law of Nature. But after all it is only an hypothesis, 
probably a very partial one, and Nature will very likely some 
day teach him that he has been too ready to narrow her 
working to the sphere of his own capacities. 
The scientific method is applicable, more or less, to all 
branches of phenomena coming within the scope of human 
understanding. But the domain claimed by Science is so 
great as to make it impossible for any man, or body of men, 
to examine it with completeness. Hence arises the necessity 
for divisions and -subdivisions in Science. The first part which 
