Transcendental arguments usually seek to demonstrate that human experience (or a particular part of human experience) has, as a necessary condition, the existence of or the belief in something. The form of the argument is simply that “there must be something Y if there is something X of which Y is a necessary condition”2 Robert Stern maintains that, strictly speaking, transcendental arguments are for a metaphysical precondition. He suggests that there are four common features in the metaphysical kind of transcendental argument. First, the claim is for a metaphysical condition usually arrived at a priori and obtains in every possible world. For example, says Stern, “existence is a condition for…