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PARTISAN REVIEW
inspired by the conception of the degrees and kinds of knowledge
expressed in the citation above from
Maritain-Philosophical Physics
by V. E. Smith. Almost the first thing we are told is that the ex–
perimental scientist cannot possibly understand motion: "Motion
eludes the cmperiological physicist . . . he cannot claim to be a
rival of the philosophical physicist in the study of the mobile world."
The reason for this is that "time and motion in emperiological physics
are not mobile."
If
this means that the conceptions of time and
motion are not mobile, of course they are not. Our concepts do not
have to move to understand motion any more than they have to
eat to understand eating.
If
the reference is to the properties and
behavior of moving things, this is precisely what physics tries to dis–
cover. Apparently, however, the fact that emperiological physics seeks
to
discover
truths about motion is a sign that it is not strict science,
indeed that it is not even strict physics because it is not a method
of proof achieving its fulfillment in speculative knowledge but "only
in the order of making inhabited by the engineer."
The criticism that modem physics is interested in discovery
rather than in proof is hardly likely to be taken as a defect by those
who believe that new discovery, the winning of new knowledge
through confirmed prediction, is at least one sign of truth. Even
proof ultimately rests on definitions or postulates. And
if
these refer
to the nature of the world, only inductive empirical procedures can
tell us whether one set of definitions or postulates is more justifiable
than any others that are conceivable. The term "intelligible," when
employed by those who criticize both cla.s;ical mechanics and rela–
tivity physics as being ontologically defective, really means "familiar."
Thus it is actually a psychological and historical concept. One man's
intelligibility is another man's paradox and a third man's absurdity.
At any rate a philosophy of nature which impugns the truth
of experimental science not in terms of findings but in terms of previ–
ously held metaphysical beliefs is not likely to give us greater insight
or more reliable truths than the magical
Natur-philosophie
to which
in some ways it is akin. I find the laws of motion, refinements aside,
much more comprehensible, much more informative about the nature
of bodies at rest and in motion, than such pronouncements of philo–
sophical physics as that "motion is a mixture of act and potency,"
which seems to be a mixture of tautology and fantasy. I do not see
