  The argument for the above conclusion – that the fundamental objects of physics cannot be regarded as individuals – can be summed up as follows: First of all, both ‘classical’ and ‘quantal’ objects of the same kind (e.g. electrons) can be regarded as indistinguishable in the sense of possessing the same intrinsic properties, such as rest mass, charge, spin etc. Consider now the distribution of two such indistinguishable particles over two boxes, or two states in general: 