 Leibniz’s account of the ideal form of metaphysics provides the basis for one of the ways that he distinguishes between the esoteric and the exoteric. In one of his earliest philosophical works, a very opinionated preface to an edition of a book by Marius Nizolius, Leibniz distinguishes between esoteric and exoteric modes of philosophizing. In this text he claims that the notion of demonstration provides the line of demarcation between the esoteric and exoteric modes. In the former “all things are demonstrated” while in the latter less rigorous forms of argumentation are utilized (e.g., supporting a proposition by means of an analogical argument). Works written in the exoteric mode, though useful in various respects, are “not most rigorous, not most exact” (A VI.ii.416). In this and other texts Leibniz equates the esoteric mode of philosophizing with the geometrical model of demonstration, as briefly described above.