_a._ We have first to remark that the name Aristotelian philosophy is most ambiguous, because what is called Aristotelian philosophy has at different times taken very different forms. It first of all signifies Aristotelian philosophy proper. As regards the other forms of the Aristotelian philosophy, however, it had, in the second place, at the time of Cicero, and specially under the name of Peripatetic philosophy, more of the form of a popular philosophy, in which attention was principally directed to natural history and to morals (Vol. I. p. 479). This period does not appear to have taken any interest in working out and bringing to consciousness the deep and properly speaking speculative side of Aristotelian philosophy, and indeed with Cicero there is no notion of it present. A third form of this philosophy is the highly speculative form of the Alexandrine philosophy, which is also called the Neo-Pythagorean or Neo-Platonic philosophy, but which may just as well be called Neo-Aristotelian—the form as it is regarded and worked up by the Alexandrines, as being identical with the Platonic. An important signification of the expression, in the fourth place, is that which it had in the middle ages where, through insufficient knowledge, the scholastic philosophy was designated Aristotelian. The Scholastics occupied themselves much with it, but the form that the philosophy of Aristotle took with them cannot be held by us to be the true form. All their achievements, and the whole extent of the metaphysics of the understanding and formal logic which we discover in them, do not belong to Aristotle at all. Scholasticism is derived only from traditions of the Aristotelian doctrines. And it was not until the writings of Aristotle became better known in the West, that a fifth Aristotelian philosophy was formed, which was in part opposed to the Scholastic—it arose on the decline of scholasticism and with the revival of the sciences. For it was only after the Reformation that men went back to the fountainhead, to Aristotle himself. The sixth signification which Aristotelian philosophy bears, is found in false modern ideas and conceptions, such as those that we find in Tennemann, who is gifted with too little philosophic understanding to be able to grasp the Aristotelian philosophy (Vol. I. p. 113). Indeed, the general opinion of Aristotelian philosophy now held is that it made what is called experience the principle of knowledge.