 Both of these arguments are subjective in the sense that, rather than attempting to show how the world must be constituted objectively in order for the highest good to be possible, they purport to show only how we must conceive of the highest good in order to be subjectively capable both of representing it as possible and of fulfilling our duty to promote it. But Kant also claims that both arguments have an objective basis: first, in the sense that it cannot be proven objectively either that immortality or God’s existence are impossible; and, second, in the sense that both arguments proceed from a duty to promote the highest good that is based not on the subjective character of human reason but on the moral law, which is objectively valid for all rational beings. So while it is not, strictly speaking, a duty to believe in God or immortality, we must believe both in order to fulfill our duty to promote the highest good, given the subjective character of human reason.