Kant, Critique of Pure Reason, A59O/B618
Kant tells us that there are exactly three ways of proving the existence of God by speculative reason. In the first, we begin from "determinate experience and the specific constitution of the world" and ascend from there to a supreme cause. "The world presents to us so immeasurable a stage of variety, order, purposiveness, and beauty" (A622/B650) that we may infer a sublime and wise cause (A625/B654). This is the physico-theological proof or argument from design. In the second, we begin from indeterminate experience or "experience of existence in general" and proceed once again to a cause. Here it does not matter what the world is like, but only that it exists; if the cosmos consisted of nothing but a speck of dust, we would still need to posit a cause for it. This is th