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WILLIAM E. CASTLE 
ers, we are permitted to go up into a high mountain and look 
over into the promised land of knowledge spread out before us 
like a map. For some of us that vision ends with college days, 
but the memory of it remains and makes us wish that our chil- 
dren may have it too, and that is why we send our sons and 
daughters to college. 
When I was a student in college two rival theories concerning 
the origin and nature of man were placed before us. Part of 
the faculty favored one theory, part the other, so we students 
had to do some thinking of our own if we reached any conclusions, 
and to think for himself is not a bad training for the student. 
According to one theory, man was not of the earth though he 
was on the earth. Heaven was his home, here he was a stranger, 
a sojourner, a wayfarer, defiled by contact with things earthly, 
trying to divest himself as rapidly as possible of the polluting 
medium in order that he might again reach a pure state. He had 
nothing to hope for in life except to make a safe escape from it. 
According to the other theory man was a product of the earth 
itself, the highest stage at present in a process of orderly develop- 
ment. Indications of what some of the earlier stages were, 
through which he had passed, were seen in the lower forms of life, 
animal or plant, or even in the rocks, which as they decay form 
soil in which plants grow, on which in turn animals feed. On 
this theory, man was no stranger here on earth but a part of a 
creative process still in progress. 
Some of us students adopted one theory, some the other, and 
I suppose today we hold much the same views that we adopted 
then. People do their best thinking, as a rule, when they are 
young, make up their minds then on fundamental questions and 
rarely change them afterward. But fortunately these same 
fundamental questions come up for study anew in every genera- 
tion and are never settled. Every student for himself can apply 
to them the try-square of truth. 
My own interest in this- question of the nature and origin of 
man led me into the study of biology and ultimately into that of 
heredity, at a time when great discoveries were being made in 
this field. It is safe to say that since 1900 more has been 
