Any one who would assert the right to a thing as his must be in possession of it as an object. It is therefore an assumption a priori of the practical reason to regard and treat every object within the range of my free exercise of will as objectively a possible mine or thine. Reason wills that this shall be recognised as a valid principle, and it does so as practical reason: and it is enabled by means of this postulate a priori to enlarge its range of activity in practice.