St. Anselm's approach was to define God as, "that than which nothing greater can be conceived". Famed pantheist philosopher Baruch Spinoza would later carry this idea to its extreme: "By God I understand a being absolutely infinite, i.e., a substance consisting of infinite attributes, of which each one expresses an eternal and infinite essence." For Spinoza, the whole of the natural universe is made of <answer>one substance, God, or its equivalent, Nature</answer>. His proof for the existence of God was a variation of the Ontological argument.
What did Spinoza believe the world was made of?
one substance, God, or its equivalent, Nature