 Nor does another point Kant makes—that Kant’s idealism concerns merely the form and not the matter of experience—constitute a clear difference from Berkeley. Berkeley does not claim that human spirits are the causes of their own ideas; he claims that God acts on human spirits, causing us to perceive an internally and inter-subjectively consistent world of ideas. Since Kant’s official doctrine in the Critique seems to require agnosticism about the ultimate nature of the things in themselves that causally affect us in experience, it is compatible with what he says that the noumenal cause of experience is God himself.