Are there individuals in physics and if so what are they?
1 : Department of Philosophy, University of Bristol
* : Corresponding author
It was once widely agreed that quantum particles violate the Principle of the Identity
of Indiscernibles and are not individuals. Simon Saunders challenged this consensus
and argued that fermions satisfy a weakened form of PII. More recently it has been
argued by Fred Muller and Michael Seevinck that even bosons are weakly discernible.
However, these authors are agreed that objects that are only weakly discernible are
not individuals. Similarly, Steven French and Decio Krause argue that quantum
particles are non-individual objects. However, it is not clear that objects being weakly
discernible is of any metaphysical significance. Also, it is not clear that naturalists
must reject primitive identity and individuality. Furthermore, are non-fundamental
objects in physics and quasi-particles to be regarded as individuals? I argue for the
real patterns account of individuals in physics and for an associated weak notion of
individuality according to which all quantum particles are individuals after all.
of Indiscernibles and are not individuals. Simon Saunders challenged this consensus
and argued that fermions satisfy a weakened form of PII. More recently it has been
argued by Fred Muller and Michael Seevinck that even bosons are weakly discernible.
However, these authors are agreed that objects that are only weakly discernible are
not individuals. Similarly, Steven French and Decio Krause argue that quantum
particles are non-individual objects. However, it is not clear that objects being weakly
discernible is of any metaphysical significance. Also, it is not clear that naturalists
must reject primitive identity and individuality. Furthermore, are non-fundamental
objects in physics and quasi-particles to be regarded as individuals? I argue for the
real patterns account of individuals in physics and for an associated weak notion of
individuality according to which all quantum particles are individuals after all.
