  In this paper I consider some logical and mathematical aspects of the
discussion of the identity and individuality of quantum entities. I shall point
out that for some aspects of the discussion, the logical basis cannot be put
aside; on the contrary, it leads us to unavoidable conclusions which may have
consequences in how we articulate certain concepts related to quantum theory.
Behind the discussion, there is a general argument which suggests the
possibility of a metaphysics of non-individuals, based on a reasonable
interpretation of quantum basic entities. I close the paper with a suggestion
that consists in emphasizing that quanta should be referred to by the
cardinalities of the collections to which they belong, for which an adequate
mathematical framework seems to be possible.
