krinon], as generally in that of the activity of the [Greek: nous apathês], Aristotle in the _de Anima_[20] is in the main but echoing the teaching of Plato.[21] ii. _Aristotle._ Plato's episodic use of logical distinctions[22] is frequent. His recourse to such logical analysis as would meet the requirements of the problem in hand[23] is not rare. In the "dialectical" dialogues the question of method and of the justification of its postulates attains at least a like prominence with the ostensible subject matter. There is even formal recognition of the fact that to advance in dialectic is a greater thing than to bring any special inquiry to a successful issue.[24] But to the end there is a lack of interest in, and therefore a relative immaturity of, technique as such. In the forcing atmosphere, however, of that age of controversy, seed such as that sown in the master's treatment of the uttered [Greek: logos][25] quickly germinated. Plato's successors in the Academy must have developed a system of grammatico-logical categories which Aristotle could make his own. Else much of his criticism of Platonic doctrine[26] does, indeed, miss fire. The gulf too, which the _Philebus_[27] apparently left unbridged between the sensuous apprehension of particulars and the knowledge of universals of even minimum generality led with Speusippus to a formula of knowledge in perception ([Greek: epistêmonikê aisthêsis]). These and like developments, which are to be divined from references in the Aristotelian writings, jejune, and, for the most part, of probable interpretation only, complete the material which Aristotle could utilize when he seceded from the Platonic school and embarked upon his own course of logical inquiry. Syllogism.