I have tried to substantiate this claim by playing a certain kind of ‘analysis game’ on a data base. It is now up to the reader to judge the success of the program. In my opinion, the data fit the hypothesis well enough – given the circumstances – for us to consider it empirically supported.

By an imprecise category I mean a category which cannot be defined in such a way that for every member x of its domain (that is, the set of things to which the category can be meaningfully applied), the definition determines a truth-value to the statement that x belongs to the category in question.