Abstract
Press a square paperweight into a lump of soft clay. What results is a square impression. Could a circular impression have resulted instead? The answer seems to be No. In this paper, I take this and similar examples as evidence for power essentialism, the thesis that the powers bestowed by a property are essential to it. I spend most of the paper trying to answer a few arguments against the evidential value of such examples: (1) there is the appearance of necessity here, but it is of the wrong sort of necessity, say, mere nomological necessity; (2) one gets the appearance of necessity only if powers (such as rigidity) are held fixed, rendering the examples useless as evidence for power essentialism; (3) the examples are too simple, too crudely mechanistic.