ABSTRACT
Often when Ockham’s razor is invoked nothing more specific is intended than the general principle that simpler theories are on the whole more probable than less simple ones. Before considering the razor itself, it is worth examining first the more general principle, often called parsimony. Often Ockham’s razor is used to argue against the position that there are things of two or more fundamental kinds by first claiming that people would not notice if one of the kinds did not exist, and then appealing to Ockham’s razor against the redundant kind. The razor has been thus employed against the dualist thesis that things come in two kinds, the mental and the physical. The authors agrees that Ockham’s razor, if accepted, puts the burden of argument on those who defend the following: theism; realism about properties and relations; realism about the subject matter of mathematics; realism about space-time; and realism about non-actual things, such as merely possible worlds.
