Whatever of positive doctrine revelation has added to natural religion transcends the reason, it is true, but does not contradict it. It contains no principles contrary to reason (whose opposite can be proved), but, no doubt, principles above reason, _i.e._, such as the reason could not have found without help from without, and which it cannot fully comprehend, though it is able approximately to understand them and to defend them against objections. Hence Leibnitz defended the Trinity, which he interpreted as God's power, understanding, and will, the eternity of the torments of hell (which brought him the commendation of Lessing), and other dogmas. Miracles also belong among the things the how and why of which we are not in a position to comprehend, but only the that and what. Since the laws of nature are only physically or conditionally necessary, _i.e._ have been enacted only because of their fitness for the purposes of God, they may be suspended in special cases when a higher end requires it. While the positive doctrines of faith cannot be proved--as, on the other hand, they cannot be refuted--the principles of natural religion admit of strict demonstration. The usual arguments for the existence of God are useful, but need amendment. The ontological argument of Descartes, that from the concept of a most perfect Being his existence follows, is correct so soon as the idea of God is shown to be possible or free from contradiction. The cosmological proof runs: Contingent beings point to a necessary, self-existent Being, the eternal truths especially presuppose an eternal intelligence in which they exist. If we ask why anything whatever, or why just this world exists, this ultimate ground of things cannot be found within the world. Every contingent thing or event has its cause in another. However far we follow out the series of conditions, we never reach an ultimate, unconditioned cause. Consequently the sufficient reason for the series must be situated without the world, and, as is evident from the harmony of things, can only be an infinitely wise and good Being. Here the teleological proof comes in: From the finality of the world we reason to the existence of a Being, as the author of the world, who works in view of ends and who wills and carries out that which is best,--to the supreme intelligence, goodness, and power of the Creator. A special inferential value accrues to this position from the system of pre-established harmony--it is manifest that the complete correspondence of the manifold substances in the world, which are not connected with one another by any direct interaction, can proceed only from a common cause endowed with infinite intelligence and power.