Book Review: Divination in the ancient world, from Plato to the Neoplatonists by way of Aristotle and the Stoics

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The word “divination” conjures mystical overtones, the existence of paranormal powers to access a divine realm, something that nowadays is the hallmark of cheap psychics in places like New York’s Greenwich Village, and whose activities are rightly relegated to the category of pseudoscience. And it is precisely that categorization that made me a little tentative before agreeing to review Peter T. Struck’s Divination and Human Nature, as understood by Plato, Aristotle, the Stoics, and the Neoplatonists. I must admit to a little prejudice, initially not seeing the point of a volume devoted to the exploration of what was clearly a dead end in ancient thought. Indeed, I accepted the assignment (from the Journal of Cognitive Historiography, where a version of this essay was published earlier this year) only because of my personal and scholarly interest in Stoicism, with little reason to expect much out of it.

I am glad to report that I was seriously mistaken. There is much in Struck’s carefully argued and well researched volume to attract the attention of anyone seriously interested in ancient philosophy, and particularly in the figures of Plato, Aristotle, Posidonius, and Iamblicus. But I would like first of all to briefly discuss the author’s general framework, which I find both novel and fruitful.

Struck effortlessly steers the course between two equally dangerous monsters: the Scylla of dismissing ancient knowledge as the result of primitive minds, and the Charybdis of accepting it as a type of lost wisdom that is somehow to be recovered and valued over and above modern science. The latter attitude is the very same one that I mentioned above and leads to the embracing of pseudoscientific notions; the former one is an error Paul Feyerabend has warned against in his intriguing posthumously published Philosophy of Nature. Plato & co. were not country bumpkins, they were brilliant human beings, equipped with the very same reasoning abilities we possess today. True, their knowledge and understanding of the world was not as advanced as ours, but it is to our peril if we too easily dismiss their insights as only historical curiosities.

Indeed, Struck’s contribution in this sense is just as much to the history of ancient philosophy as it is to the history of science, and more broadly the history of human thought. It makes sense of why rationally and/or empirically minded people of the first caliber (Plato, Aristotle) devoted so much time and effort to thinking about the nature of divination, something we dismiss as obvious superstition.

To better grasp Struck’s fundamental point, we need to recall that the ancient Greeks and Romans distinguished two approaches to divination. On the one hand there were the “professional” diviners, the priests who were in charge of reading signs of the future into natural events, ranging from the entrails of animals to the flight patterns of birds. On the other hand, there were people that, for unknown reasons, appeared to have the gift of seeing signs of future events, usually in the midst of altered states of consciousness, like dreams.

In a sense, then, professional divination was considered a science, based on the reasonable premise that if the world includes gods who have plans to steer or otherwise interfere with human events, then there ought to be reliably interpretable signs of divine activity that would help us foresee where things may be going. The Stoics in particular brought this line of reasoning further, on the basis of their materialist and deterministic understanding of the world. For them everything was made of matter, including the “soul” and “god,” by which they meant the rational principle underlying the cosmos and which permeates the entire universe. Moreover, since the world inexorably works by a widespread web of cause-effect relations, then it makes perfect sense to think that one can arrive at a science of divination based on systematic observations aimed at uncovering correlations. Indeed, as Struck points out in the chapter on Posidonius, the Stoics were aware of what we today consider the distinction between correlation and causation, but sensibly argued that even in the absence of causal knowledge one can still use correlational evidence for practical purposes. (Modern statisticians often quip that correlation is not causation, but the two are highly correlated…)

For instance, in book I of Cicero’s De Divinatione, we are treated to a dialogue with Cicero’s brother, Quintus, who plays the part of the Stoic, based on an original source that very likely is Posidonius (Cicero himself was an Academic Skeptic, though he sympathized with the Stoic position). In response to a direct question, Quintus says: “I consider that the outcomes of these practices should be investigated rather than their causes,” because the causes are inaccessible to Stoic “physics,” one of the three Stoic topoi, which included what moderns class as the whole of the natural sciences, metaphysics, and theology.

But what should one make of the non-professional type of divination? Here Struck proposes a fascinating reading key, referring to it as “surplus knowledge,” and treating it as part of the history of our understanding of the phenomenon of intuition. In this respect, it is interesting to contrast how Plato and Aristotle accounted for non-professional divination, each from within the general scheme of his philosophy, rationalistically minded in the first case, more empirically grounded in the second one. Plato, not surprisingly, does not think highly of divination, especially the non-professional variety. The reason is that in his account divination is a type of non-discursive knowledge, of which we do not have a sensible explanation, and that arrives unexpectedly and unsystematically. For a philosopher who put the highest premium on mathematical rationality, this ought to be the lowest possible form of knowledge. But it is knowledge nonetheless, which is why Plato does discuss it, in several of his dialogues, including the Apology, Phaedrus, Phaedo, and the Symposium. As for the professional divination, in Ion and in Statesman, Socrates considers it a kind of technical skill, similar in nature to those of doctors, charioteers and fishermen.

Moreover, Struck points out that both in the Charmides and the Laches, Plato describes divination as a form of particular knowledge that does not have the benefit of a broader conception of things, like the one afforded by philosophy. He is also aware, interestingly, of the existence of charlatans motivated by personal gain, just as is the case today. As the author points out:

Taken together, these references to the technê and office of the diviner tell us of a person to be less admired than philosophers and law-abiding rulers, but more admired than poets, sophists, or tyrants. (Struck, p. 46)

More pertinent to Struck’s suggestion that non-professional divination should be considered as analogous to intuition is his analysis of Plato’s language in the Laws, where the verb that conveys the meaning of “divining” is a synonym for “surmise” or “intuit.” In this sense, divination for Plato is like peripheral vision: fuzzy, of unclear origin, but nonetheless a type of knowledge.

Even more fascinating is Struck’s observation that in Charmides Socrates suggests that temperance — one of the four cardinal virtues (the other three being practical wisdom, courage, and justice) — is good. He does so without developing a formal argument, however, but rather stating that he “divined” the conclusion. That is, he has arrived at it by way of (philosophical) intuition.

The Meno makes it even more clear that divination is not knowledge, but something more akin to what we call intuition:

Then if it isn’t knowledge, the thing left is right opinion; by using this thing statesmen guide their cities, and they are no different with respect to their knowledge than oracles and manteis [people who do divination]. For these men also in an inspired state say many true things, and yet they know nothing of what they’re saying. (99b-c)

Struck argues, convincingly, I think, that Socrates’ famous daimonion, the “voice” that tells him if he is right or wrong about something, is described in several dialogues in a fashion very reminiscent of the practice of non-professional divination, that is, again, intuition.

But why would non-professional diviners get their glimpse of the future when they experience altered states of consciousness, like dreams? The answer is best articulated in the Timaeus:

And when, in turn, a certain inspiration from discursive reasoning paints opposite images of gentleness, and provides a respite from the bitterness, because it refuses to move or to touch what is naturally opposite to it, and by using the sweetness innate throughout the liver, and by setting it all back into correct alignment, making it smooth and unencumbered, it makes the part of the soul settled around the liver gentle, and it is in good order. And it passes the night in a measured state, experiencing divination during sleep, since it has no share of reason and purposive intelligence. (71c-d)

In other words, it is when we are asleep that we are least affected by the rational component of the soul, and are thus most receptive to other sources of knowledge, which we perceive from the universe via the lower soul.

By contrast with Plato, who writes often about divination, but in scattered places throughout his dialogues, Aristotle writes little about the topic, and most of it is concentrated in a single treatise: On Divination During Sleep. Aristotle, interested in empirical evidence as he is (again, in contrast with Plato) is at the same time skeptical of divination, and yet thinks that there are too many good examples of it to dismiss the idea outright. Interestingly, he notices, divination by dreams — what I have here referred to as the non-professional type — is not done by the wisest or most intelligent or educated people, but by individuals belonging to the common masses. like Plato, and in classic Aristotelian aristocratic fashion, he thinks that this is due to the fact that lay people use their higher faculties far less than the best and wisest, so that there is less interference by the rational mind on the natural powers of divination.

One more contrast with Plato is that Aristotle attempts to provide an entirely mechanistic explanation of divination, in a sense foreshadowing the Stoics:

Aristotle then sets out the mechanics for how future-leaning dreams could work, saying that it may be that something at a distance from us disturbs the air nearby it, and that this disturbance then stirs up the air adjacent to it, and so on in turn, until the movement reaches the sleeping soul, like a ripple traveling over water. (Struck, p. 98)

Moreover, these instances occur at night (during sleep) because under those circumstances the air is less turbulent, thus more likely to carry the faint disturbances more reliably. Again:

Aristotle frames the glimmers of insight that come through divinatory dreams as examples of a peculiar cognitive capacity built into the rudiments of the human organism. The knowledge resulting from it is nondiscursive, and not the result of selfconscious deliberation or volition. It is a surplus that is accessible to all of us, but for most people the higher-order intellects occlude this lower-order information processing system. The lower one realizes itself just in the special case of those who have weak higher-order ones. (Struck, p. 104)

I find it interesting that Struck builds a comprehensive argument, which unfortunately I have no space to adequately summarize here, that Aristotle denies that dreams are simply sent by the gods. His interpretation is more subtle. Dreams are “demonic” but not divine occurrences. “Demonic” here refers to a diffuse type of divine activity, not targeted on purpose by the gods in order to favor specific individuals, but more like an inherent feature of the (ultimately divine) nature of the universe. The demonic, as Struck (p. 121) says, is “a way for Aristotle to talk about the projection of divine power into the natural world.” In a sense, then, Aristotle provides a conceptual bridge — halfway between the divine and the naturalistic — between Plato’s more abstract metaphysical views and the very much materialist take of the Stoics, for whom god is nature, and to whom I now return.

The Stoics had a very different conception of the cosmos from both Plato and Aristotle, and this has obvious implications for their interest in divination. The entire universe was considered to be a living organism, with each part — including every individual human being — partaking in the Logos of the whole. This, together with the above mentioned materialist metaphysics, makes it relatively straightforward for the Stoics to account for both professional and non-professional divination.

Struck explains that the Stoics thought that god is a sort of “fine mist,” the pneuma (or breath), which permeates everything. There are, however, four levels of pneuma, so to speak, each unequivocally labelled by its own technical word. The lower level gives coherence to inanimate matter, the second one holds together plants (and, interestingly, the human fetus), the third gives animals the power of sensation and movement, and the highest one provides humans with reason and speech.

Unlike Plato [the Stoics], propose that the contiguous character of the whole creates otherwise inexplicable connections between things, analogous to the connections between sometimes distant parts of a single organism. […] These interconnections are the central innovation of the Stoic school that is relevant to the topic of divination, and they consistently travel under the same technical term. The Stoics label this property of the cosmos ‘sympathy.’ (pp. 179–80)

It is an elegant solution to the problem of divination, springing from the sophisticated, coherent philosophical system that is Stoicism.

One of the most interesting characteristics of the Stoic view of divination is that they connected it with the idea of Fate: in their deterministic, cause-and-effect universe nothing happens on its own, things are interconnected. That being the case, it follows that events ought to be predictable, either because one can study and grasp the web of causes and effects (indirectly, by paying attention to correlations, as in professional divination), or because, being part of the cosmic organism, one “senses” the reverberations throughout some parts of the web (non-professional divination by way of altered states of consciousness). Indeed, the character of Quintus is quite explicit in this regard:

If there were a man whose soul could discern the links that join each cause with every other cause, then surely he would never be mistaken in any prediction he might make. For he who knows the causes of future events necessarily knows what every future event will be. But since such knowledge is possible only to a god, it is left to humans to presage the future by means of certain signs that indicate what will follow them. (De Divinatione I.127)

Quintus even defines divination as the prediction of events that are thought to occur by chance, but which quite clearly cannot actually happen by chance, in a deterministic universe. The Stoics in general — in a very modern fashion — defined chance (tychê) as a cause that is unclear to human reason.

The last part of Struck’s tour de force of the idea of divination as surplus knowledge in the ancient world deals with Neoplatonism, and specifically Iamblichus. I think here we reach a turning point, after which divination in the original sense begins to be considered a type of pagan superstition and criticized, and later even persecuted, by Christians. In fact, for Neoplatonists “real” divination is something radically different from the conception articulated by the ancient Greeks, as it is presented as a way of escaping from the material world and accessing a higher truth about the inherent structure of the universe.

Accordingly, even the venerable figure of the Oracle takes on a completely different meaning, again reflecting a sharp break with tradition. The Oracle is no longer consulted to provide glimpses of future events, but rather to regale us with insight into the nature of the divine. The fascinating thing is that while some of the reasons for this shift in how to see the role of oracles has cultural and philosophical roots, the shift also occurred as the result of accident. Struck reminds us that people’s conception of the Sibylline Oracle in Rome, for instance, changed after the fire of 6 July 83 BCE, which destroyed the temple of Jupiter Optimus Maximus, and with it the sacred books that were traditionally used to interpret the Oracle.

The Neoplatonist move away from the material world, and the quest for a more direct access to the divine, is of course rooted in the Platonic idea that the material world is but a pale reflection of the world of Forms, and Iamblichus in particular embarks on a program of re-conceiving divination accordingly. As Struck highlights:

Iamblichus is at pains to try to separate his program from manipulative sorcery and mere wonder working. […] Iamblichus moves on to do something his predecessors had never done. He makes two broad categories in divination, and draws a distinct line between ‘true’ or ‘divine’ or ‘authentic’ mantikê, of the kind which he has been describing, as opposed to the lesser forms of sign reading that derive from the material world. (pp. 234, 236)

In a sense, this is Plato on steroids, since the earlier philosopher did grant a status to divination as a source of knowledge, but of a very imperfect kind. Iamblichus is out to delegitimize it further, in order to replace it with his own conception.

In the end, Iamblichus concludes that divination in the traditional sense is on par with the natural sciences, which is something that the Stoics would not be entirely unhappy with. But unlike the Stoics, Iamblichus also concludes that both divination and the natural sciences are unreliable sources of knowledge, mere guesswork, and that they ought to be subordinate to approaches that give us direct insight into the nature of the divine. From there the step is short in order to arrive at the dominant view of science as the subordinate handmaiden of theology which characterized the Christian Middle Ages.

Struck has succeeded in putting together an accessible yet scholarly volume that cannot fail to captivate students of ancient Greek philosophy, people interested in the history of ancient divinatory practices, as well as those who are keen on finding the roots of modern concepts — such as intuition and surplus knowledge — in the sophisticated systems of thought that have preceded the modern era. The book truly is a historical and philosophical treasure trove, and it deserves wide attention.

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