26 ILLINOIS ACADEMY OF SCIENCE 
bish from the priceless results of generations of experience. It 
is also a spirit that demands a close connection between a 
result and its claimed cause. Failure to develop this spirit 
provides the soil in which political demagoguery, destructive 
charlatanism, and religious vagaries flourish like noxious 
weeds. It is a spirit that keeps one close to the facts. One of 
the hardest things in my teaching experience has been to check 
the tendency to use one fact as a starting point for a wild flight 
of fancy. Such a tendency is corrected somewhat, of course, 
when facts accumulate, and flight in one direction is checked 
by a pull in some other direction. Most of us, however, have 
the tendency, and the majority are so unhampered by facts that 
flight is free. There seems to be abroad a notion that one may 
start with a single well attested fact, and by some machinery 
of logic construct an elaborate system and reach an authentic 
conclusion, much as the world imagined for more than a cen- 
tury that Cuvier could do if a single bone were furnished him. 
The result is bad, even though the initial fact has an unclouded 
title, but it too often happens that great superstructures have 
been reared upon a fact that is claimed rather than demon- 
strated. 
Facts are like stepping-stones; so long as one can get a 
reasonably close series of them, he can make some progress in 
a given direction; but when he steps beyond them he flounders. 
As one travels away from a fact its significance in any given 
conclusion becomes more and more attenuated, until presently 
the vanishing point is reached, like the rays of light from a 
candle. <A fact is really influential only in its own immediate 
vicinity ; but the whole structure of many a system lies in the 
region beyond the vanishing point. 
Such “vain imaginings” are delightfully seductive to many 
people, whose life and conduct even are shaped by them. I 
have been amazed at the large developmnt of this phase of 
emotional insanity, commonly masquerading under the name 
“subtle thinking.” Perhaps the name is expressive enough if it 
means thinking without any material for thought. An active 
mind turned in upon itself, without any valuable objective ma- 
terial, seems to react upon itself, resulting in a sort of mental 
chaos. In short, the scientific spirit is one that makes for 
