 The modern tradition of natural kinds begins with J. S. Mill (1884) who talked of ‘Kinds’ (the term ‘natural kind’ is traced by Hacking (1991a) back to Mill’s contemporary, the logician John Venn (1866)). According to Mill, typical singular (individual) names such as ‘Scott’ denote their referents but lack any connotation, that is to say the names do not imply any attribute. Some singular names do have connotation as well as denotation, for example ‘the author of Waverley’. A general name, such as ‘white’, denotes all the things they hold of (its extension) while also connoting the attribute they all share in common. Natural kind terms are a special case of general terms in this respect