natural concept which proves its reality in the objects of sense, given (or which may possibly be given) before all natural concepts; or to the concept of freedom, which sufficiently establishes its reality through the causality of Reason in regard of certain effects in the world of sense, possible through it, which it incontrovertibly postulates in the moral law.

The natural concept (merely belonging to theoretical cognition) is now either metaphysical and thinkable completely a priori, or physical, i.e. thinkable a posteriori and as necessary only through determinate experience. The metaphysical natural concept (which presupposes no determinate experience) is therefore ontological.

The ontological proof of the being of