Logical and epistemological problems in quantum theory
I examine some logical and epistemological problems
arising in quantum theory. Two historical episodes are
considered in detail: Planck's adoption of the quantum
hypothesis and Heisenberg's discovery of matrix mechanics.
The former episode is, I argue, more compa tLbLe with
logical empiricist views of scientific progress than it is
with more recent and currently influential philosophies.
My examination of the latter concerns the influences -
epistemological as well as.sci~ntific- which may have
affected the manner in which Heisenberg chose to present.
his discoveries; these considerations a~low me to rebut ...
the suggestion that Heisenberg's practice was incompatible
with his professed views and to counter the claim that this
episode provided unwarranted support to formalistic ideas
concerning scientific explanation.
The connexions between Bohr's principle of
complementarity and logical empiricist views concerning
language change in science are explored, and I argue that
the transition from classical to quantum mechanics· can be
seen as involving a shift in the meanings of "position"
and "momentum" so that these terms obtain unambiguous
empirical meanings from the viewpoint of quantum· theory.
Discussing the relevance of quantum mechanics to logic
I contend that, although classical logic may be retained,
empirical considerations may make it advisable to adopt a
non-classical logic for quantum theory.
An analysis of Bell' s inequality.:is a prelude to
some speculations concerning the interpretation of quantum
theory. I examine the possibility of interpreting the
formalism as descriptive not of an external world but of
the expectati.ons of subjects. The final chapter explores
the relevance of physics to questions concerning human
freedom. Classical physics, I argue, did not have the
devastating implications for personal autonomy that it was
often assumed to have; quantum physics does not explain .
human freedom but, under certain assumptions, it does show
how it is possible.