to other knowledge.

A scientist is one who has learned to organize his knowledge. The main
difference between a scientist and one who is not a scientist is that
the scientist sees the significance of facts, while the non-scientific
man sees facts as more or less unrelated things. As one comes to hunt
for causes and inquire into the significance of things, one becomes a
scientist. A thing or an event always points beyond itself to something
else. This something else is what goes before it or comes after it,--is
its cause or its effect. This causal relationship that exists between
events enables a scientist to prophesy. By carefully determining what
always precedes a certain event, a certain type of happening, a
scientist is able to predict the event. All that is necessary to be able
to predict an event is to have a clear knowledge of its true causes.
Whenever, beyond any doubt, these causes are found to be present, the
scientist knows the event will follow. Of course, all that he really
_knows_ is that such results have always followed similar causes in the
past. But he has come to have faith in the uniformity and regularity of
nature. The chemist does not find sulphur, or oxygen, or any other
element acting one way one day under a certain set of conditions, and
acting another way the next day under exactly the same conditions. Nor
does the physicist find the laws of mechanics holding good one day and
not the next.

The scientist, therefore, in his thinking brings order out of chaos in
the world. If we do not know the causes and relations of things and
events, the world seems a very mixed-up, chaotic place, where anything
and everything is happening. But as we come to know causes and
relations, the world turns out to be a very orderly and systematic
place. It is a lawful world; it is not a world of chance. Everything is