 As noted above, Spinoza accepts the basic Cartesian view that physical things are res extensa—extended things. However, whereas Descartes held that distinct bodies are distinct extended substances, Spinoza famously holds that there is but one substance—God or nature—and that distinct bodies are merely modes of this one substance, considered as extended. Spinoza's substance monism is in part motivated by inadequacies in the Cartesian view. Descartes officially defines substance in terms of independence: a substance is that whose existence depends upon no other thing. But only God satisfies this definition, all other beings depending on God for their existence. So Descartes also allows for finite substances—minds and bodies—that are dependent only upon God. But it is only in an equivocal sense that both God and created, finite bodies and minds are substances. Spinoza will have none of this. For him, independence is the sine qua non of substance, and nothing that is not its own cause — nothing whose existence is not of its essence—is independent. Hence nothing finite and created is substantial. Further, since everything is either in itself or in another (Ia1), finite things like bodies are in substance, that is, they are in some way features of the one substance.