Similarly, it seems that pure practical reason should be motivating even without a guarantee that its object will be satisfied in full with God's help. Kant does have an answer to this, though. For there must be some reason to think that pure practical reason's use at least makes bringing its object about more probable, if pure practical reason's use is to make sense. But Kant will not accept any contingent or a posteriori justification of the use of pure reason. Even if we could argue that in this world, the goodwill of society rewards the just, Kant would reject this as too empirical to be relevant to ethics and demand his postulates with an a priori guarantee.