of the system gradually gathered around the original kernel of ethics. But knowing Stoicism only as we do from the form which it attained after the time of Chrysippus, it will be enough, in analysing that form, to proceed from without to within, and to advance from logic through natural science to ethics. When this has been done it will be time to go back over the same ground, and to explain how from the ethical tone of Stoicism its peculiar speculative tenets may be deduced. CHAPTER V. LOGIC OF THE STOICS. [A. General remarks.] [(1) Field of logic.] Under the head of Logic, in the Stoic use of the term after the time of Chrysippus, a number of intellectual enquiries are included which would not now be considered to belong to philosophy at all. One common element, however, characterised them all—they all referred to the formal conditions of thought and expression. Logic was primarily divided into two parts, sharply marked off from each other, roughly described as the art of speaking continuously and the art of conversing. The former is known as Rhetoric, the latter as Dialectic. [112] To these two was added, as a third part, the doctrine of a standard of truth, or the theory of knowledge; and, according to some authorities, [113] a fourth part, consisting of enquiries into the formation of conceptions. By others, these enquiries were regarded as the third main division, the theory of knowledge being included under dialectic. [114] By rhetoric, however, little else was meant than a collection of artificial rules, of no philosophical value; [115] and dialectic was in great measure occupied with enquiries referring to precision of expression. Dialectic is defined to be the science or art of speaking well; [116] and since speaking well consists in saying what is becoming and true, [117] dialectic is used to express the knowledge of what is true or false, or what is neither one nor the other, [118] correctness of expression being considered inseparable [(2) Words and thoughts.] from correctness of thought. Words and thoughts are, according to this view, the very same things regarded under different aspects. The same idea (λόγος), which is a thought as long as it resides within the breast, is a word as soon as it comes forth. [119] Accordingly, dialectic consists of two main divisions, treating respectively of utterance and the thing uttered, thoughts and words. [120] Both divisions, again, have several subdivisions, [121] which are only imperfectly known to us. [122] Under the science of utterance, which was generally placed before the science of things uttered, [123] are included, not only instruction as to sounds and speech, but also the theories of poetry and music, these arts being ranked under the head of the voice and of sound on purely external considerations. [124] What is known of the teaching of the Stoics on these subjects, consisting, as it does, of a mass of definitions, differences, and