Full Idea
Elements defined by their atomic numbers are frequently assumed to represent 'natural kinds' in chemistry. ...The question arises as to whether groups of elements appearing in the periodic table might also represent natural kinds.
Gist of Idea
If elements are natural kinds, might the groups of the periodic table also be natural kinds?
Source
Eric R. Scerri (The Periodic Table [2007], 10 'Elements')
Book Reference
Scerri,Eric R.: 'The Periodic Table' [OUP 2007], p.280
A Reaction
Scerri says the distinction is not as sharp as that between the elements. As a realist, he believes there is 'one ideal periodic classification', which would then make the periods into kinds.