  We discuss some methodological aspects of the relation between physics and
metaphysics by dealing specifically with the case of non-relativistic quantum
mechanics. Our main claim is that current attempts to productively integrate
quantum mechanics and metaphysics are best seen as approaches of what should be
called `the metaphysics of science', which is developed by applying already
existing metaphysical concepts to scientific theories. We argue that, in this
perspective, metaphysics must be understood as an autonomous discipline. It
results that this metaphysics cannot hope to derive any kind of justification
from science. Thus, one of the main motivations of such project, which is the
obtaining of a scientifically respectable justification for the attribution of
a single true metaphysical profile to the posits of a scientific theory, is
doomed because of the emergence of metaphysical underdetermination from the
outset. If metaphysics floats free from physics, which is a premise of such
project of integration between these two areas, then it is always possible to
attribute more than one metaphysical profile to dress physical entities.
