THE PRESIDENT'S ADDRESS. 
311 
lence of what may be termed, in contradistinction to the mental 
habitudes of former times, the Scientific Spirit is another j and the 
question naturally arises, What are we to understand by this ex- 
pression 1 
Now I think it will be readily understood that some things may 
be known as great realities, but yet by reason of their impalpable 
nature and subtle operation may not be susceptible of any verbal 
description that shall convey a real knowledge of them to those 
who have not the culture, or are not in local circumstances, to per- 
ceive their presence. Human thought is always in excess of the 
powers of language. An atmosphere must be breathed to be appre- 
ciated, and so the prevalence of the Scientific Spirit is a matter rather 
of mental recognition than of verbal explanation. In any obser- 
vations I may make, I shall therefore have to assume that all 
educated men are somewhat familiar with that of which I speak. 
Upon this subject one thing is very clear — the nature of the 
Modern Scientific Spirit can scarcely be considered and understood 
apart from the method which has done more than anything else to 
develope it. In the development of the human mind bare know- 
ledge of items of fact, and a few crude and isolated ideas, precede 
definite methods of research. When thoughtful men, unacquainted 
with any literature or stores of knowledge, began for the first time 
to study the complex whole called the world, they were already 
possessed of a few vague ideas, the result of the unmethodized 
impressions of youth and manhood. Prepossessed with a stock of 
notions and unverified principles, they began, as in the case of the 
Ionic speculators, to find, if possible, out of a superficial observa- 
tion of scanty facts, a bond or principle that held all things together, 
and accounted for their forms. Aristotle and Plato were indepen- 
dent and irreverent enough to set aside the theories sanctioned by 
venerable names ; and although Aristotle formulated a distinct in- 
ductive method, he brought to the study of Nature too many 
preconceived ideas, and failed to verify inductions based on partial 
facts. In subsequent ages the great error lay in assuming, when 
about to explore the nature of things, that certain abstract concep- 
tions, already arrived at by a most uncritical generalization, were 
the mental archetypes with which external realities must correspond; 
and as years rolled on these mental archetypes gradually became 
more and more dominant, because associated with venerable names 
that in a too credulous age were synonymous with authority. If 
