154. The Stoics are naturally reluctant to admit that doctrines which it is impious to deny are nevertheless unattainable except by perfect wisdom; but their whole system points inevitably to this conclusion. But there are intermediate stages between the rough inborn outlines of these truths and their ripe completeness. As man grows in reason, he becomes increasingly able to appreciate contributory truths, derived from the combination of perception and reasoning, that is, by processes such as ‘analogy’ and ‘comparison,’ which point in the direction of the supreme beliefs. In this sense, and (it is here suggested) in this sense only, can there be ‘proofs’ (ἀποδείξεις) of these[67]. Only in the crowning moment of that probation which is described later on, at the moment of conversion, these truths finally flash forth, stirred up indeed by secondary evidence, but really rooted in the man’s deepest nature[68]; they then reveal themselves to the soul with an illuminating power which is all their own, but which carries with it the most complete conviction. Ordinary men must meanwhile somehow make shift with reflections or pale copies of this knowledge, to which however the name of common or inborn notions can also be applied.
The inward touch.
155. The list of ‘common notions’ is doubtless not limited to the high philosophical principles which we have mentioned; for instance it must include such mathematical principles as ‘two and two make four,’ ‘a straight line is the shortest distance between two points,’ ‘a three-sided figure has three angles,’ and so forth. With these however we have little direct concern. Of more interest to us is another kind of perception[69] recognised by the Stoics as well as by other schools of philosophy, that called the ‘inward touch’ (ἐντὸς ἁφή)[70]. By this the soul becomes aware of its own workings, most obviously of its pleasure and pain. The doctrine of the ‘inward touch’ is of great philosophical importance, for it breaks down the dualism of subject and object, the barrier between the knowing and the known. Since these are the same in the specific cases named, the door is open to the conclusion that everywhere there is a kinship between the two, and that without this knowledge would be without firm foundation. By this kinship we may also explain the fact that direct communications are made by the deity to man, as by dreams, oracles and augury[71].
Knowledge; the parts and the whole.
156. Thus it appears that the elements of knowledge, according to the Stoics, are sensations, perceptions, conceptions or notions, and general or inborn notions. As in the other parts of the Stoic philosophy, we shall regard this fourfold division as indicating generally the ground covered, and not as setting up definite lines of demarcation. The same material may be analyzed from other points of view, as for instance in the study of words, in which we shall find a division into objects, statements, conditional statements, and syllogisms. The elements may also be combined in various ways. A combination or ‘system’ (σύστημα) which is directed towards a useful or pleasurable object, such as music or grammar, is called an ‘art’ (τέχνη, ars)[72]; and arts are attainable by ordinary men. The wise man, on the other hand, is not necessarily acquainted with the several arts; his practice is to ‘keep quiet’ when matters are discussed which require such special knowledge. The combination of all knowledge in one all-embracing system is ‘science’ (ἐπιστήμη, scientia); the only science in the full sense is philosophy[73]; and in this system no part can be at variance with any other part[74]. The elements of knowledge also acquire the character of science, when they are found to be parts of this compacted system, and therefore incapable of coming into conflict with any other part[75]; and in particular we find the term ‘science’ predicated of comprehensions which are firmly established and cannot be refuted by any argument[76]. In the language of Zeno’s simile, over the closed fist that grasps the object is placed the other hand, keeping it with firmness and assurance in its place[77]; or, to use a comparison first suggested in ridicule of Stoicism, but which by the progress of architectural skill has since then been made less damaging, science is like a firm and immoveable building constructed upon a shifting foundation[78]. Finally ordinary men can reach comprehension, but only the wise man can attain to science[79].
The criterion reviewed.
157. We revert to the difficult problem of the criterion of truth, that is, the discovery of a rule by which the true can separated from the false. Our authorities differ greatly as to what the Stoic criterion is; and this vacillation must have placed the Stoics at a great disadvantage in their controversy with the Academics, who maintain that there is no criterion. The most usual statement is that the ‘comprehensive mind-picture’ (καταληπτικὴ φαντασία) is the criterion; this view is expressly attributed to Chrysippus, Antipater, and Apollodorus[80]. As we have seen, the meaning of this is that a true mind-picture can be distinguished from one that is false by the note of clearness, and this general doctrine can be traced back to Zeno[81]. It appears at first sight to provide a criterion which can be applied by the percipient at the moment when it is needed, and it was doubtless intended to be a practical tool in this sense; but under the pressure of criticism the Stoics were frequently compelled to modify it. They could not but admit that in the case of dreams and drunken visions it is only at a later moment that the lack of clearness can be appreciated[82]; whereas on the other hand a picture may be perfectly clear, and yet the percipient, because of some prepossession, may not realize this. Such was the case when Hercules brought Alcestis from the world below; her husband Admetus received a true mind-picture of her, but put no confidence in it, because he knew her to be dead. It follows that no mind-picture can be implicitly trusted for itself; for our sense organs may be clouded, or our previous experience in conflict with it. If the Academics urged that the sure note of clearness is not to be found in the senses[83], the Stoics admitted as much when they now said that a true comprehensive picture must come from a real object[84], when they added the words that ‘no objection must arise[85]’; thus really admitting that it must be not only persuasive, but also such as no reasoning process can shake, and such as has been examined from all sides[86]. Thus they shifted the centre of certainty from the single comprehension to the general field of science; they still held to it in theory, but no longer maintained its practical application. For this too they had the authority of the older masters. For we learn on the authority of Posidonius that ‘some of the older Stoics’ held the true criterion to be ‘right reason’ (ὀρθὸς λόγος)[87], and this is equivalent to saying that only the deity and the wise man possess the secret[88]. In a loose sense any important part of the Stoic theory of reason may be said to be a criterion; thus Chrysippus again said that ‘the criteria are sensation and preconception,’ and Boethus set up many criteria, as mind, sense, science, and (in practical matters) appetite[89].
General consent.
158. Seeing that the full assurance of truth is not at every moment attainable, it is necessary to be contented from time to time with something less complete. Amongst such tests the ‘general consent of mankind’ plays an important part, especially in connexion with the dogma ‘that gods exist.’ We may indeed well believe that this criterion was not originally suggested by revolutionary philosophers, but rather by conservative advocates of an established religion; and therefore we are not surprised to see it emphasized first by Posidonius and afterwards by Seneca[90]. General consent is however by itself no proof of truth, but at most an indication of the presence of a ‘common notion’ in its rough shape. If however we see that the ‘common notion’ grows stronger and more clear every day, and if it is the more firmly held as men approach the standard of wisdom, it becomes a strong support[91].
Probability the guide of life.