Alone among Aristotle's four causes, the dynamic of material causation cannot be ascribed to God when it comes to creation. The material cause is that 'out of which' something comes to be, and creation is not made out of God. God is, however, the cause of materiality. Discussion of these themes allows us to see the profound difference between accounts of participation and notions of pantheism or panentheism. It also opens up a discussion of what it means for creatures to be 'substantial': they have real being, but it is not self-grounded being; they have being, but it is being had from another.