All paths on which one may set forth with this aim either begin from determinate experience and the special constitution of our world of sense known a through it, and ascend from that by means of laws of causality to the highest cause outside the world; or else they are empir ically grounded on an experience that is only indeterminate,.e., on some existence; or, finally, they abstract from all experience and infer the existence of a highest cause entirely a priori from mere concepts.