LVI PHILOSOPHICAL SOCIETY OF WASHINGTON. 
Heraclitus proclaimed that the Universe with all it contains sprang 
into being from elemental heat, and was destined to be resolved 
again into the elemental heat from which it sprang, and thus in a 
ceaseless round to continue the cycle of being, he taught a doctrine 
of conservation and correlation of energy which had its root in 
metaphysical physics. When Dr. John Tyndall declares that “all 
our philosophy, all our poetry, all our science, all our art—Plato, 
Shakespeare, Newton, and Raphael—are potentially in the fires 
of the sun,” and so tucks away the genius of a Darwin in the folds 
of a nebular blastema, he teaches a doctrine of equivalence which 
has its root in physical metaphysics. 
It will thus be seen that under the dominion of Science the world 
has use for as much metaphysic as ever before, but only for a meta- 
physic radically different from the old metaphysic in its point of 
departure as also in the tests of its validity, and, therefore, radi- 
cally different in the tenure by which it is held. The votaries of 
the old metaphysical physics proceeded from what was unknown to 
explicate and explain the known appearances of things, and rested 
content in explanations which seemed to consist with those appear- 
ances. The votaries of the modern physical metaphysics proceed 
from what is known to explicate and explain what is unknown in 
the deeper relations of things, and rest content in explanations only 
so long as, and so far as, they seem consistent with experimental 
proofs or with the broadest homologies of the deductive reason. 
When the law of simple multiples in chemical combinations was 
given to the world by Dalton, and was expressed by him in atomic 
language, he had really made a great departure from the physical 
methods of Democritus, though it is curious to observe that there is 
a perfect identity between the metaphysical ideas underlying his 
logic and the metaphysical ideas of his Greek predecessor. The 
method of each proceeds on the assumption of the indestructibility 
of matter, and it is from this platform that the English chemist 
reaches out his hand to the Greek philosopher in token of a com- 
mon metaphysic. “No new creation or destruction of matter,” 
wrote Dalton, in his celebrated paper on “ Chemical Synthesis,” “is 
within the reach of chemical agency. We might as well attempt 
to introduce a new planet into the solar system, or to annihilate 
one already in existence, as to create or destroy a particleof hydro- 
