39 (3):483–504 (2005
An electron clearly has the property of having a charge of þ1.6 10 19 coulombs, but does it also have the property of being charged ? Philosophers have worried whether so-called ‘determinable’ predicates, such as ‘is charged’, actually refer to determinable properties in the way they are happy to say that determinate predicates, such as ‘has a charge of þ1.6 10 19 coulombs’, refer to determinate properties. The distinction between determinates and determinables is itself fairly new, dating only to its definition by the Cambridge logician W. E. Johnson early in the last century.1 But despite its newly minted condition the distinction has found little currency in on-going philosophical debates. Or at least until recently. Renewed interest in realist positions about properties, and arguments that the determinable-determinate relation may hold the key to understanding mental causation, have thrust Johnson’s distinction to the fore. With this new attention has also come new ‘optimistic’ positions that endorse the existence of determinable properties. David Armstrong, Evan Fales, and Sydney Shoemaker, among others, have all defended such optimistic accounts that take determinable predicates, such as ‘is charged’, to refer to determinable properties.2 In this paper, our goal is to carefully assess optimism and to argue that a pessimistic view, which rejects the existence of determinable properties, is actually the appropriate default position.