ANNUAL ADDRESS OF’ THE PRESIDENT, 
J. W. Powe tt, 
Delivered December 8, 1883. 
THE THREE METHODS OF EVOLUTION. 
In the early history of research attention was chiefly given to 
phenomena of co-existence. In late years the phenomena of sequence 
have received the larger share of attention. The investigation of 
the phenomena of sequence has led to.the invention of a number of 
hypotheses. In the past history of scientific research three of these 
have each led to a long series of important discoveries. These are 
the nebular hypothesis, the atomic hypothesis, and the hypothesis 
of the development of life. The nebular theory is an hypothesis 
of astronomic evolution; the atomic theory has gradually assumed 
the shape of an hypothesis of chemical evolution; and the develop- 
ment theory has been elaborated and re-stated as the hypothesis of 
biologic evolution. The time has come when in all fruitful research 
evolution in some form is postulated by each investigator in his own 
field. Yet many scientific men, though admitting the doctrines of 
evolution in their own special fields, ofttimes reject them elsewhere; 
and there is some disagreement even among the greatest thinkers 
as to the extent to which the hypotheses of evolution can be carried, 
but all postulate evolution in some form and to some degree. 
An attempt will be made in this address to point out what is be- 
lieved to be the fact—that there are three grand classes of phe- 
nomena, constituting three kingdoms of matter and representing 
three stages of evolution; or, stated in another way, that there has 
been an evolution of the methods of evolution, so that the methods 
discovered in the first stage have been superseded by those discov- 
red in the second, and these superseded by the methods of the third 
stage. It is proposed to indicate and, as clearly as possible within 
the limits of an address, to define, in terms of matter and motion, 
the three kingdoms of matter and the three methods of evolution. — 
As precedent to the general statement it will be well, therefore, 
briefly to consider the kinematic hypothesis. 
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