If the thought-forms could in fact have attained the form of content, they would have been a content of thought in itself. But as they were they had value as laws of thought (λεκτά)[135] merely. The Stoics indeed had a system of immanent determinations of thought, and actually did a great deal in this direction; for Chrysippus specially developed and worked out this logical aspect of things, and is stated to have been a master in it (_supra_, pp. 240, 241). But this development took a very formal direction; there are the ordinary well-known forms of inference, five of which are given by Chrysippus, while others give sometimes more and sometimes fewer. One of them is the hypothetical syllogism through remotion, “When it is day it is light, but now it is night and hence it is not light.” These logical forms of thought are by the Stoics held to be the unproved that requires no proof; but they are likewise only formal forms which determine no content as such. The wise man is specially skilful in dialectic, we are told by the Stoics, for all things, both physical and ethical, are perceived through a knowledge of logic.[136] But thus they have ascribed this perception to a subject, without stating who this wise man is (p. 250). Since objective grounds by which to determine the truth are wanting, the ultimate decision is attributed to the will of the subject; and this talk about the wise man consequently has its ground in nothing but the indefiniteness of the criterion, from which we cannot get to the determination of content.
It would be superfluous to speak further of their logic any more than of their theory of judgments, which in part coincides with it, and in part is a grammar and a rhetoric; by it no real scientific content can be reached. For this logic is not, like Plato’s dialectic, the speculative science of the absolute Idea; but, as formal logic, as we saw above (p. 254), it is science as the firm, secure, unalterable comprehension of reasons, and stops short at the perception of the same. This logical element, whose essence consists pre-eminently in escaping to the simplicity of the conception to that which is not in opposition to itself nor falls into contradiction, obtains the upper hand. This simplicity, which has not negativity and content in itself, requires a given content which it may not abrogate—but consequently it cannot thus attain to a genuine “other” through itself. The Stoics have constituted their logic often in the most isolated fashion; the principal point that is established here is that the objective corresponds to thought, and they investigated this thought more closely. If in a manner it is quite correct to say that the universal is the true, and that thought has a definite content that must also be concrete, the main difficulty, which is to deduce the particular determination from the universal, so that in this self-determination it may remain identical with itself, has not been solved by the Stoics: and this the Sceptics brought to consciousness. This is the point of view most important in the philosophy of the Stoics; it thus showed itself in their physics also.