There’s an interesting short paper by Paul Bloom and Susan Gelman in the July issue of Trends in Cognitive Science with that title. Unfortunately, it’s not yet available without a subscription (though Bloom tends to put his papers on his website once published, so it might show up there sometime in the near future), but if you have a subscription or access to a university library, you can read it here.
If you’re not familiar with the idea, “psychological essentialism” is the belief that entities have an internal set of necessary properties, or an essence, that make them what they are. For example, people tend to believe that there’s something about tigers (their DNA, perhaps) that make them tigers. There’s a great deal of evidence that people are “psychological essentialists” about natural kinds (animals, elements, that sort of thing), and a growing body of evidence that we tend to be psychological essentialists when it comes to certain social categories as well, like gender, race, and sexual orientation.
Bloom and Gelman relate the story of the selection of the 14th Dalai Lama, in which those doing the selection presented a child with objects that the 13th Dalai Lama had owned, as well as similar objects, and observed which of the objects the child selected. Since he picked all of the objects that had belonged to the Dalai Lama, he was chosen to be the 14th, and current Dalai Lama. They conclude:
Our point here is not that the authentic objects were actually imbued with the essence of the 13th Dalai Lama (a metaphysical question that is beyond the scope of our inquiry). What matters is that the Tibetan bureaucrats believed that the objects were. Hence they constructed a procedure that presupposes the existence of invisible essences – essences that require special powers to perceive – and used this procedure to make a decision of major importance. We take this as evidence of the ubiquity, naturalness and importance of psychological essentialism. (p. 243)
Bloom, P. & Gelman, S.A. (2008). Psychological essentialism in selecting the 14th Dalai Lama. Trends in Cognitive Science, 12(7), 243.