low partly totally different, partly the
same, elementary laws of force. Material atoms are subordinate to the law
of gravitation, while atoms of ether are not; and yet both act legitimately
upon one another,--as, for instance, when heat passes into motion and
motion into heat, which certainly presupposes a law of power acting in
common for both. Another difficulty lies in the atomism of the chemists;
and still another {143} in the divergency of the aims at which the physical
theory of atoms on the one hand and the chemical theory of atoms on the
other seem to point. Chemistry is inclined to explain the difference of its
numerous elements from the original difference of the atoms; and yet it is
not at all certain that the elements of chemistry themselves are not
composed of still more simple and less numerous primary elements. Many
indications seem to point to such primary elements which are more simple in
number and quality, and investigators even mention an element--hydrogen--in
the direction of which we have to look for the way that will lead us to
those primitive elements of matter. The divergency of aims, finally,
consists in the fact that physical atomism prevailingly points to a
conformity of the atoms of bodies; chemical atomism, on the contrary,--at
least, according to its present state,--points to a dissimilarity among
these.

The hypothetical and problematical nature of the theory of atoms strikes us
still more clearly when we try to analyze it philosophically. First, we
meet that antinomy which we always find where we try to pass beyond the
limits of our empirical knowledge by means of conception. For, if the atoms
still occupy space, we can not understand why they should not be further
divisible, and if they do not occupy space, we can not understand how any
sum of that which does not occupy space, can finally succeed in filling
space. It is true, this very antinomy has led to the overcoming of that
dualism of force and matter which so long enchained science, and the
overcoming of which we greet as a progress of our theoretical knowledge of
nature. We no {144} longer look upon the atoms as material elements, but as
centres of force. The antinomy has the further merit that, in the realm of
the knowledge of nature, it brings to our consciousness the great advantage
of a concrete perception and reasoning over purely logical abstractions.
For Ulrici, in his "God and Nature," is right in calling our attention to