Natural kind

A natural kind is a grouping of things which is a natural grouping, not an artificial one. Often are biological species or chemical elements mentioned as examples. Natural kinds may be distinguished from, for example nominal kinds (such as numbers) and artifacts (such as cars and furniture). It is however, controversial whether natural kinds exists, whether, for example, biological species are natural classes or social constructions.


"Natural kinds provide a system for classifying objects. Scientists can then use this system to predict and explain the behaviour of those objects. For these reasons, the topic of natural kinds is of special interest to metaphysics and to the philosophy of science". (Daly, 1998).


Keil (1987) suggests that natural kinds have greater richness and internalization of homeostatic structure, while nominal kinds are more well defined. Artifacts have attributes which lie between those of pure natural kinds and those of pure nominal kinds.


Prinz & Clark (2004, p. 68): "Much work in philosophy of mind and language has focused on concepts of natural kinds, where the main point has been that we are able to represent a category despite how little we know about it. If we place action guiding representations at the center, we may end up with different theories. We may discover in hindsight that natural kind concepts, which once seemed so pristine are action-oriented as well".


LaPorte (2004)  argues that scientists do not discover that sentences about natural kinds are true rather than false. This applies, for example, to the sentence "Whales are mammals, not fish". Instead, scientists find that these sentences were vague in the language of earlier speakers, and they refine the meanings of the relevant natural-kind terms to make the sentences true. Hence, scientists change the meanings of those terms. LaPorte's view is opposed to the received view in which the language used to refer to natural kinds in scientific discourse remains stable even as theories about these kinds are refined.  LaPorte's view also differ from the Quinean view of language according to which there is no difference between a change in language and a change in theory. "Just as a theory can change without meaning, meaning can change without theory" (p. 147).






Daly, C. (1998). Natural kinds. IN: Routledge Encyclopedia of Philosophy, Version 1.0, London: Routledge


Keil, F. C. (1989). Concepts, Kinds, and Cognitive Development. Cambridge, MA.: The MIT Press.


LaPorte, Joseph (2004). Natural Kinds and Conceptual Change. Cambridge: Cambridge University Press.


Machery, E. (2005). Concepts are not a natural kind. Philosophy of Science, 72(3).


Prinz, J. & Clark, A. (2004). Putting Concepts to Work: Some Thoughts for the Twentyfirst Century. Mind & Language, 19(1), 57–69. Available at:


Wikipedia. The free encyclopedia. (2006). Natural kind.


Wilkins, J. S. (2003). How to be a chaste species pluralist-realist: the origins of species modes and the synapomorphic species concept. Biology & Philosophy, 18(5), 621-638.




See also: Artificial versus natural classification;  Species; Typology



Birger Hjørland

Last edited: 04-08-2008