Roman Stoicism being lectures on the history of the Stoic...

143. The history of Greek philosophy, even before the time of Zeno, leads naturally to its division into the three parts of logic, physics, and ethics[1]. The Ionic philosophers had chiefly occupied themselves with the nature and history of the universe, that is, with the problems of physics. The sophists were greatly concerned with questions as to the validity of human knowledge, that is, with logic. Socrates shared this interest, but attached greater importance to the discussion of moral activities, that is, to ethics. It is however not clear when a formal division into these three parts was first made. Cicero attributes it to the immediate followers of Plato in the Academic school; others assign it definitely to Xenocrates[2]. The Peripatetics and Stoics both adopted the division, but whereas the former assigned to Logic an inferior position, making it an introduction to philosophy, the Stoics insist that it is a part of philosophy itself[3]; and that of the three parts it comes first in the order of study, ‘as in the measuring of corn we place first the examination of the measure[4].’ It must not however be thought that the three parts of philosophy can be separately treated, for they are intertwined[5]; so that in treating of Logic we shall constantly have need to assume a general knowledge of Stoic views both on physics and ethics. Logic is subdivided into ‘dialectic,’ which deals with reasoning, and ‘rhetoric,’ the art of speech.

144. Stoicism, as one of the positive and dogmatic schools, assumes that knowledge is attainable. Since this is the very point on which Socrates never reached assurance, except on the one particular that he himself knew nothing, it was a matter of primary importance to the Stoics to make good this position; more especially since they held (this time in agreement with Socrates) that virtue is but another form of knowledge. Yet the Stoics could not agree with the Cynics, that true knowledge can be imparted without a study of its method[6]. Knowledge is, in their view, a high privilege derived by man from his divine ancestry, and shared by him with the deity alone; and the whole duty of man may be summed up by saying that he should keep upright his reason[7]. They therefore devoted themselves with special zeal to this part of philosophy[8], and were accordingly nicknamed ‘the dialecticians[9].’ Their aim in this was solely the ascertainment and imparting of truth; but the common view that their style was in consequence harsh and repellent will be found to need considerable qualification[10].

145. The chief argument for the certainty of knowledge is that we assume as much in the practical affairs of life[11]; and (as we have already seen) Aristo found it ridiculous that his Academic neighbour should not even know who he was[12]. Against it is the fact that men frequently disagree even as to what they see, and commonly distinguish between what is known to them and what ‘seems’ to be this or that. Hence Epictetus well defines the function of dialectic as

‘a perception of the disagreement of men with one another, and an inquiry into the cause of this disagreement; a condemnation and distrust of that which only seems, and some kind of investigation of that which seems, as to whether it rightly seems: and the discovery of some rule (κανών)[13].’

Of all kinds of knowledge that which comes through the senses appears to the ordinary man most worthy of confidence, and of the five senses that of sight seems to the philosopher the most divine[14]. In consequence, the whole controversy hinges on the question whether the eyes can be trusted. The positivist argues that the evidence of sight is so plain and unmistakeable that man, if he had the choice, could wish for no better informant. The sceptic replies that nevertheless, if a straight oar be placed partly in the water, it appears to the eyes to be bent; and that the feathers on a dove’s neck, though really alike, appear to the eyes as many-coloured[15]. To deal with such questions we must examine closely the nature of sensation.

146. The Stoics fancifully derive the word αἴσθησις (‘sensation’) from εἴσθεσις (‘storage’); it is therefore, strictly speaking, the process by which the mind is stored[16]; but it is also, from an opposite point of view, the process by which the mind reaches out towards an external object[17]. From the object (αἰσθητόν) proceed waves which strike upon the sense-organ (αἰσθητήριον); this impact is called a ‘sensation’ in a narrower sense. At the same time there proceeds from the mind (which is the ruling part or ‘principate’ of the soul), a ‘spirit’ or thrill which goes out to meet this impact; and this spirit and its operation are also called ‘sensation[18].’ As a result of the contact of these two waves, and simultaneously with it, there is produced in the soul an effect like the imprint of a seal[19], and this imprint is the φαντασία or ‘mind-picture.’ That the process may be sound, it is necessary that the intellect be in a healthy state, and further that the organ of sense be healthy, the object really there, and the place and the manner in accord[20]. But we must carefully distinguish between the single sensation and the mind-picture. A flash of light, a cry, a touch, a smell, a thrill of pleasure or pain, is always that which the senses declare it to be[21]; here there is no possibility of error; so understood ‘the sensations are always true[22].’

But if we go in each case a step further; if we say ‘that is white,’ ‘this is sweet,’ ‘this is musical,’ ‘this is fragrant,’ ‘that is rough,’ we are now dealing with mind-pictures, not with ‘sensations’ in the strict sense[23]. And as to the mind-pictures we agree with the Academics that things are not always what they seem; ‘of the mind-pictures some are true, some are false[24].’

147. In order then that we may distinguish the true mind-picture from the false, we have need of a ‘rule’ (κανών) or ‘criterion’ (κριτήριον). The true mind-picture is a stirring of the soul, which reveals both what is taking place in the soul and the object which has caused this: just as light reveals both itself and the objects that lie within its range[25]. On the other hand the false mind-picture is an empty twitching of a soul which is not in a healthy condition[26]; no real object corresponds to it, but to that which appears to be an object corresponding to it we give the name ‘phantasm[27].’ When Orestes thinks he sees the Furies leaping upon him, though his sister assures him that in real truth he sees nothing, the vision of the Furies is a phantasm. The appearances of dreams are equally phantasms[28]. Now a true mind-picture differs from that of a phantasm by being clearer; or, in other words, the distinctive note of a true mind-picture is its ‘clearness’ (ἐνάργεια, perspicuitas)[29]. Clearness then is a quality which attaches itself to a true vision in a way in which it can never attach itself to a work of phantasy[30]. To this clearness the mind cannot but bow[31]; it is therefore (so far as our study has proceeded) the criterion of truth[32].

148. The mind-picture as such is not within a man’s control; but it rests with him to decide whether he will give it his ‘assent’ (συγκατάθεσις, adsensio or adsensus)[33]. This assent is therefore an act of the soul, in its capacity as will; and can only be rightly exercised by a soul properly strung, that is, possessed of due tension. Assent wrongly given leads to ‘opinion’ (δόξα, opinio), and all wrong assent is error or ‘sin’ (ἁμαρτία, peccatum). This error may take place in two directions, either by a hasty movement of the will (προπίπτειν), giving assent to a picture which is not really clear; or by feebleness of will, which leads to assent in a false direction (διαψεύδεσθαι)[34]. Even haste however is a form of weakness, so that we may say that all opining is a weak form of assent[35]. To ensure a right assent due attention should be given to each of its parts; it includes (i) the intention of mastering the object (πρόθεσις); (ii) careful attention directed to the object, or ‘application’ (ἐπιβολή); and (iii) assent in the narrower sense[36]. Apart from assent, three courses remain open: these are (i) ‘quiescence’ (ἡσυχάζειν, quiescere): (ii) ‘suspense of judgment’ (ἐπέχειν, adsensum sustinere), which is a settled quiescence; and (iii) negation[37].

149. Close upon assent follows ‘comprehension’ (κατάληψις, comprehensio): this is the ratification of the assent given, the fixing irrevocably in the mind of the picture approved. This picture now becomes a ‘comprehension-picture’ (καταληπτικὴ φαντασία), and as such a unit of knowledge. We may understand thereby that the mind has grasped the external object[38], and this is the plain meaning of Zeno’s simile; or we may say that the object has gained a hold upon the mind, and has left its stamp upon it. Both interpretations are consistent with Stoic doctrine: but the former view, which represents the soul as active and masterful, undoubtedly expresses the more adequately the meaning of the school[39]. From this mutual grasp there follows an important physical deduction. Since only like can grasp like, the soul must be like the object, and the popular dualism of mind and matter is (to this extent) at an end[40]. Still this likeness is not complete; and the soul in sensation does not grasp the object from every point of view, but only so far as its own nature permits in each case[41]. For this reason the trained observer and the artist grasp far more of the object than the ordinary man[42].

150. The soul, having grasped single mind-pictures, retains its hold upon them by memory[43]; the frequent exercise of which keeps each picture fresh and complete[44]. As the air, when an orchestra is performing, receives the impression of many sounds at the same time, and yet retains the distinctive tone of each[45], so the soul by concurrent alterations of its texture preserves its hold on the separate pictures it has once grasped. Fresh operations of soul now supervene. First, from the comparison of many like pictures, comes ‘experience’ (ἐμπειρία, experientia)[46]; out of other comparisons, ‘similitude’ (ὁμοιότης), as ‘Socrates’ from his portrait; and ‘analogy’ (ἀναλογία, proportio), as ‘the centre of the earth’ from that of other spheres; ‘transference’ (μετάθεσις, translatio), as ‘eyes in the heart’; ‘composition’ (σύνθεσις, compositio), as ‘a Hippocentaur’; ‘opposition’ (ἐναντίωσις, transitio), as ‘death’ from life; ‘deprivation’ (κατὰ στέρησιν), as ‘a cripple[47].’ All these are based on the general principle of likeness and unlikeness, and may be summed up under the general heading of ‘reason’s work of comparison’ (collatio rationis)[48], or shortly, of reason (λόγος)[49]. Sensation shews us the present only; but reason brings the past and the future within our view, and points out to us the workings of cause and effect[50].

151. With the mind-pictures (φαντασίαι, visa) which are derived from sensation we may now contrast the ‘notions’ (ἔννοιαι, notiones or intellegentiae) which are derived from the combination of sensation and reasoning; the former correspond generally to ‘perceptions,’ the latter to ‘conceptions’ in the language of modern philosophy[51]. But each of the Stoic terms is also used in a wider sense which includes the other. The sensory pictures are inscribed upon the mind as upon a blank sheet from birth upwards; in this sense they may well be called ‘entries on the mind’ (ἔννοια from ἐν νῷ)[52]. On the other hand the conceptions may be called ‘rational mind-pictures’[53]; quite as much as the sensory mind-pictures they need the prudent assent of the will before they become ‘comprehensions,’ when they are once more units capable of entering into further combinations and becoming part of scientific knowledge. If then for the sake of clearness we use the modern terms, we may say that perceptions correspond generally to individual objects which have a real existence, whilst conceptions correspond to classes of things, which (according to the Stoics) have no real existence in themselves, but only a sort of existence in our minds. Thus the ‘ideas’ of Plato are all conceptions, subjectively but not objectively existent[54].

So far as our study has gone, all conceptions are based on perceptions: therefore all the elements of knowledge either come from sense and experience solely, or from sense and experience combined with reasoning[55]; and the most important reasoning process is that comparison of like perceptions which in this philosophy takes the place of induction[56].

152. But even if all ‘conceptions’ are ultimately derived from ‘perceptions,’ it does not follow that in each particular case the mind commences de novo to collect and shape its material. On the contrary, it is clear that not only all practical life, but also all philosophy, takes for granted a great many matters which are either allowed by general consent, or at least assumed by the thinker; and these matters are mostly of the nature of class-conceptions. If it is stated that ‘the consul entered Rome in a chariot drawn by four horses,’ we assume that the ideas expressed by ‘consul,’ ‘chariot,’ ‘four,’ ‘horses,’ are matters of general consent, and we may go on to assume that the person of the consul and the locality called ‘Rome’ are also already known to the speaker and his hearers. The general term in the post-Aristotelian writers for such legitimate assumptions is ‘preconception’ (πρόληψις, anticipatio or praesumptio). The precise meaning of this term (of which the invention is ascribed to Epicurus[57]) appears not to be always the same. Most commonly the ‘preconception’ is a general term or conception, and therefore to the Stoics it is one variety of the ἔννοια; it is ‘a mental shaping, in accordance with man’s nature, of things general’[58]. All such preconceptions are foreshadowings of truth, especially in so far as they correspond to the common judgment of mankind[59]; and the art of life consists in correctly applying these presumptions to the particular circumstances with which each individual man has to deal[60].

As to the nature of a preconception, there is a great difference between Epicurus and the Stoics. Epicurus identifies all the terms ‘preconception,’ ‘comprehension,’ ‘right opinion,’ ‘conception,’ and ‘general notion,’ and maintains that each of these is nothing but memory of a sensation frequently repeated[62]; the Stoics however hold that preconceptions are established by the mind[63], and (so far as they are common to all men) by the universal reason. This difference is fundamental. Epicurus, as a materialist in the modern sense, explains perception as a bodily function, and ‘conceptions’ of every kind as mere echoes of such bodily functions. The Stoics on the other hand recognise at each stage the activity of mind, and this in increasing degree as we proceed to the higher levels of thought.

153. We now approach the most critical point in the Stoic theory of knowledge. Is it possible for man to possess knowledge which is not derived, either directly or indirectly, through the organs of sense? Such a question cannot be answered by any appeal to single Stoic texts; it needs an appreciation of the whole philosophic outlook, and upon it depend the most vital principles of the system. Let us then first consider, on the supposition that such knowledge exists, what its nature is, what its content, and how it is attained by individual men. Knowledge cut off from the sense-organs is cut off from all human individuality; it is therefore the expression of the common reason (κοινὸς λόγος), and its parts are ‘common notions’ (κοιναὶ ἔννοιαι or προλήψεις), shared by gods and men, but by men only so far as they are partakers of the divine nature. The principal content of such knowledge is also clear; it includes the conception of what is morally good, and the beliefs that gods exist and that the world is governed by their providence[64]. Lastly, as of all general conceptions, the rudiments or rough outlines only of these beliefs are inborn in men, by virtue of their divine ancestry; whence they are called ‘innate notions’ (ἔμφυτοι ἔννοιαι, insitae notiones)[65]. These notions in their full development are not attainable by children at all, nor by men till they attain to reason, that is, till they become wise men[66].

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.

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].

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].

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].