by the power of the dialectic it makes use of hypotheses, not as principles but only as hypotheses—that is to say, as steps and points of departure in order to reach a region above hypotheses, the first principle of all” (which is in and for itself), “and clinging to this and to that which depends on this, it descends again to the result, for it requires no sensuous aid at all, but only ideas, and thus it reaches the ideas finally through the ideas themselves.” To know this is the interest and business of Philosophy; this is investigated by pure thought in and for itself, which only moves in such pure thoughts. “I understand you, but not perfectly. You seem to me to wish to assert that what is contemplated in Being and Knowledge through the science of dialectic is clearer than what is contemplated by the so-called sciences which have hypotheses as their principle, and where those who contemplate them have to do so with the understanding and not with the senses. Yet because in their contemplation they do not ascend to the absolute principle, but speculate from hypotheses, they appear not to exercise thought (νοῦν) upon these objects, although these objects are cognizable by thought if a principle is added to them (νοητῶν ὄντων μετὰ ἀρχῆς). The methods (ἕξιν) of geometry and its kindred sciences you appear to me to call understanding; and that because it stands midway between reason (νοῦς) and ‘sensuous’ opinion (δόξα).”—“You have quite grasped my meaning. Corresponding to these four sections, I will suppose four faculties (παθήματα) in the soul—conceiving reason (νόησις) has the highest place (ἐπὶ τῷ ἀνωτάτῳ), understanding the second; the third is called faith (πίστις)”—the true conception for animals and plants in that they are living, homogeneous and identical with ourselves; “and the last the knowledge of images (εἰκασία),” opinion. “Arrange them according to the fact that each stage has as much clearness (σαφηνείας) as that to which it is related has truth.” This is the distinction which forms the basis of Plato’s philosophy, and which came to be known from his writings.