|Natural Kinds, philosophy: deviating from the biological definition, substances such as gold, water, etc. are referred to as natural kinds in the recent philosophical discussion. This goes back to the way in which these terms were introduced. (See H. Putnam, “The Meaning of 'Meaning”'. In Philosophical Papers, Vol. 2. Mind, Language and Reality, Cambridge.) Starting from a primary showing, the natural kind is defined as "something like this". The decisive point here is that there is no limit to future research. Virtually, any property that is initially attributed can prove to be a false assumption. See also introduction, definitions, terms.|
Books on Amazon
Properties/Kind/Millikan: propoerties exist only in the actual world (our real world).
Natural kinds/Putnam/Millikan: Thesis: at least in the case of natural kind-concepts, the intension does not determine the extension.
Reason: it is possible that such concepts have identical intensions but different extensions.
Meaning/Putnam: whatever has different extensions, must have different meanings. Therefore, meanings cannot be in the head.
Putnam/Millikan: his argumentation here is that of a realist.
Meaning/Millikan: if meanings are not intensions, there must be something else that can determine the reference or the extension.
Natural kind/solution/Putnam: contrary to the appearance natural kind-concepts are indexical. And tradition has always had its difficulties with this.
Extension/Putnam: Thesis: the extension of "water" and "gold" is determined by a relation between the expression token and the extension.
MillikanVsPutnam: that is the reason why he mistakenly thinks that natural kind-concepts are indexical. No problem is solved, but only one is named.
R. G. Millikan
Language, Thought, and Other Biological Categories: New Foundations for Realism Cambridge 1987