The Process of Induction

Experience, Reason, Knowledge, Grasping Universals

"All animals have an inborn discriminatory power, called perception. If perception is present, in some retention of the perception comes about, but in others not. ... When this happens many times, a difference comes about, so that some come to have reason from the retention, and others not. From perception comes memory, and from memory (when it occurs often in connection with the same thing), experience; for memories many in number form a single experience. From experience, from the whole universal that has come to rest in the soul (the one apart from the many, whatever is one and the same in all those things), there comes a starting-point of art and of knowledge, of art if it deals with coming to be and of knowledge if it deals with being. Thus the states [that grasp starting-points] neither belong in us in a determinate form, nor come about from other states that are more cognitive; but they come about in us from perception—as in a battle when a rout occurs, if one man makes a stand another does and then another, until a starting-point is reached. The soul is such as to be capable of undergoing this. ... So it is clear that it is necessary to cognize the firsts by induction; for perception instills the universal in this way" (Posterior Analytics II.19.99b).

"By nature all men reach for knowledge. ... Animals are by nature born with the power of perception, and from this some acquire the faculty of memory, whereas others do not. ... The other animals live by impressions and memories, and have but a small share of experience; but the human race lives also by art and reasoning. It is from memory that men acquire experience, because the numerous memories of the same thing eventually produce the effect of a single experience. Experience seems very similar to knowledge and art, but actually it is through experience that men acquire knowledge and art. ... Art is produced when from many thoughts from experience a single universal judgment is formed with regard to like objects. To have a judgement that when Callias was suffering from this or that disease this or that benefited him, and similarly with Socrates and various other individuals, is a matter of experience; but to judge that it benefits all persons of a certain form, considered as a class, who suffer from this or that disease (for example, the phlegmatic or bilious when suffering from burning fever) is a matter of art" (Metaphysics I.980a).

"It would seem that for practical purposes experience is in no way inferior to art; indeed we see men of experience succeeding more than those who have theory without experience. The reason is a that experience is knowledge of particulars, but art of universals; and actions and the effects produced are all concerned with the particular. For it is not man that the physician cures, except incidentally, but Callias or Socrates or some other person similarly named, who is incidentally a man as well. So if a man has theory without experience, and knows the universal, but does not know the particular contained in it, he will often fail in his treatment; for it is the particular that must be treated. Nevertheless we consider that knowledge and proficiency belong to art rather than to experience, and we assume that artists are wiser than men of mere experience (which implies that in all cases wisdom depends rather upon knowledge); and this is because the former know the cause, whereas the latter do not. For the experienced know the fact, but not the wherefore; but the artists know the wherefore and the cause. For the same reason we consider that the master craftsmen in every profession are more estimable and know more and are wiser than the artisans, because they know the reasons of the things which are done; but we think that the artisans, like certain inanimate objects, do things, but without knowing what they are doing (as, for instance, fire burns); only whereas inanimate objects perform all their actions in virtue of a certain natural quality, artisans perform theirs through habit. Thus the master craftsmen are superior in wisdom, not because they can do things, but because they possess a theory and know the causes (Metaphysics I.1.981a).

Aristotle says that practitioners "know (ἴσασι) the fact," but presumably he is is talking about the judgment in the language people ordinarily use to talk about it.




"There are men that are doctors, we say, and others that are doctors' assistants; but we call the latter also, to be sure, by the name of doctors. These, whether they be free-born or slaves, acquire their art under the direction of their masters, by observation and practice and not by the study of nature—which is the way in which the free-born doctors have learnt the art themselves and in which they instruct their own disciples" (Plato, Laws IV.720a).
Aristotle does not think reason is inborn. he thinks that as human beings become adults, they naturally acquire reason in a causal process he calls "induction" (ἐπαγωγή).

Human Beings Acquire Reason

Aristotle thinks Plato was right to conceive of reason in terms of the possession of certain concepts and the knowledge that constitutes the possession of these concepts.

Aristotle thinks that perception is the first step in the casual process that results in reason in human beings. He thinks that all animals have the power of perception and the power to act in terms of these perceptions. Some animals, as they mature, develop the ability to remember what they perceive. From these memories, some develop what Aristotle calls "experience" (ἐμπειρία). This is thinking that allows them to react to their perceptions in a more nuanced way. From experience, humans develop reason and the knowledge that belongs to it.

It is easy to get confused about the role of experience here.

Suppose that in a geometry class we are given a proof that the interior angles of a triangle sum to two right angles. The premises in the proof function as evidence for the conclusion, but these premises do not say anything about the experiences of looking at or touching toy triangles we might have had in school as children. So the proof does not cite these or any experiences we might have had as evidence for the truth of the conclusion.

These experiences, though, might be necessary for us to understand the proof because it might be that we would not possess the concepts of triangle, angle, and so on, without them.

If this is true, then although the experiences we had as children do not function as evidence for the knowledge the proof gives us, these experiences enable us to have this knowledge.

In the causal process Aristotle describes, "experience" enables us to have reason and its knowledge. We do not get this knowledge by drawing conclusions from our experience. Drawing conclusions is an activity of reason and so is not yet possible for us.

It follows that children do not have reason and do not engage in reasoning.

Experience and Reason

We still need a clearer explanation of the ability someone possesses when he has "experience."

There is a passage in his Metaphysics that provides some help.

In this passage, Aristotle uses an example from medicine to distinguish the ability "experience" provides from those that "art" (τέχνη) and "knowledge" (ἐπιστήμη) provide.

The translations of τέχνη and ἐπιστήμη here can be confusing.

The crucial point is about grasping universals. Experience does not provide this ability. Art and knowledge does. Someone with an "art" grasps universals in connection with "coming-to-be," and someone with "knowledge" grasps universals in connection with "being."

In his example, Aristotle refers to the two types of medical doctors in ancient medicine.

The medical practitioner can make the "judgement that when Callias was suffering from this or that disease this or that benefited him, and similarly with Socrates and various other individuals" because he has lots of experience with the disease and its treatment.

The medical theorist is more advanced. He can make the more sophisticated judgment that "it benefits all persons of a certain type, considered as a class, who suffer from this or that disease (for example, the phlegmatic or bilious when suffering from burning fever)."

This more sophisticated judgment involves a grasp of a universal.

Although the medical practitioner can make a diagnosis in circumstances in which the layman is more likely to make a mistake, he does not grasp the universal the theorist knows is common to the patients who have a certain disease and benefit from a certain treatment. The practitioner does not conceive of the disease in terms of a universal, such as being phlegmatic. He notices the disease in terms of how his patients look, and he acquired this ability on the basis of his experience in seeing patients with the disease. This ability is a matter of perception and memory, not the kind of thinking Aristotle understands as reason.

Aristotle's point is not that the practitioner has less clinical success than the theorist. The practitioner can have experience sufficient for him to discriminate all and only the patients who have a certain disease and who will benefit from a certain treatment. What distinguishes him from the theorist is his inability to grasp the universal. The practitioner does not grasp "the why and the cause" Aristotle thinks is necessary for "art" and "knowledge."

This conception of "art" and "knowledge" can seem surprising to us.

We think that knowledge requires the knower be in a special position with respect to the proposition he knows. Contemporary philosophers sometimes make this point by saying that knowledge requires justification. We would find it natural to say that Aristotle's medical practitioner has knowledge because he has justification. If we challenge his diagnosis or the remedy he prescribes, he can point to past success in treating patients whose disease he identifies in terms of the way it looks. This can provide us with confidence that the practitioner is correct, but Aristotle does not think the practitioner has "art" or "knowledge" because he does not grasp the universal in the matter in which he has "experience."

We will consider Aristotle's notion of "knowledge" in more detail in a subsequent lecture.

Purposeful Behavior and Choice

Aristotle draws a parallel distinction between purposeful behavior and "choice" (προαίρεσις).

Animals and children are capable of purposeful behavior. They can discriminate among things in their environment and act in ways that tend to benefit them. This behavior, however, according to Aristotle, is not making a "choice" because it is not an exercise of reason.

"Now animals are by nature born with the power of sensation, and from this some acquire the faculty of memory, whereas others do not. Accordingly the former are more sensible and capable of learning than those which cannot remember. Such as cannot hear sounds (as the bee, and any other similar type of creature) are sensible (φρόνιμα), but cannot learn; those only are capable of learning which possess this sense in addition to the faculty of memory. Thus the other animals live by impressions and memories, and have but a small share of experience; but the human race lives also by art and reasoning" (Metaphysics I.1.980a).

"In the other animals choice does not exist, nor in man at every age or condition; for neither does deliberating and judgment about the why. It is possible that many have an opinion whether a thing is to be done, but not through reasoning" (Eudemian Ethics II.10.1226b21). We will consider Aristotle's conception of "choice" in more detail in a subsequent lecture.

The Perfection of Reason

The battle metaphor (in the passage in II.19 of the Posterior Analytics in the side note above) Aristotle uses to explain what happens in the transition from "experience" to "reason" is difficult to interpret, but it suggests that the acquisition of reason is not a matter of grasping universals one by one in isolation. If this interpretation is right, then Aristotle thinks that the grasping of universals does not take place without the advent of knowledge of the necessary connections of consequence and incompatibility between the universals grasped.

This makes it natural to think of reason as something that can be improved and perfected. Reason and its knowledge initially consists of a grasp some basic set of universals as we become adults, but we can improve and perfect our reason by grasping universals in other domains.

This means that "experience" can occur at different times in life. As a human being becomes an adult, experience is part of the process of induction that results in the possession of reason and its knowledge. Experience, however, can also occur later in the life when someone perfects his reason by extending his grasp of universals to other domains and parts of reality. The medical practitioner has taken the first step in this process. He has what Aristotle calls experience because that he acquired by engaging in careful observation of patients and outcomes.

More of the Solution

Given this understanding of Aristotle's theory of induction and the acquisition of reason in human beings, it is possible to understand his teleology a little more clearly.

The problem is to explain why natural bodies of a given kind behave as they do, but since these ways of behaving are beneficial for them, the explanation cannot make the regularity of the connection between the behavior and its being better for them be a coincidence.

Aristotle rejects explanations in the Anaxagorean style because they make the regularity of the connection between the behavior and its value a coincidence. Aristotle concludes that the "for something and because it is better" (Physics II.8.198b) is somehow present in nature.

Aristotle explains how a natural body has its behavior in terms of its form. The form is the organization of the material so that there is a natural body of the kind. The body has the potential to behave in ways that characterize the species because of the organization in the material. If the material is organized in the form of a rational animal, then the body has the potential to acquire reason. This happens in the causal process Aristotle calls induction.

Somehow, then, the form is "for" this behavior "because it is better."

The question is how.

Aristotle's answer is not easy to understand. It involves the first unmovable mover and the causal role Aristotle thinks this first mover plays in the explanation of change in the cosmos.

Aristotle's first unmovable mover is the subject of the next lecture.




Perseus Digital Library

Plato, Phaedo, Theaetetus
Aristotle, Eudemian Ethics, Metaphysics.

Henry George Liddell, Robert Scott, A Greek-English Lexicon

γνωρίζω, gnōrizō, verb, "gain knowledge of, become acquainted with, discover,"
ἐμπειρία, empeiria, noun, "experience"
ἐννοέω, verb, "reflect upon, consider"
ἐννοηματικός, ennoēmatikos, adjective, "notional"
ἔννοια, noun, "notion, conception"
ἐπαγωγή, (from ἐπᾰ́γω = ἐπι +‎ ἄγω),
καθόλου, (= καθ᾽ ὅλου), katholou, adverb, "on the whole, in general"
λογισμός, logismos , noun, "counting, calculation"
συλλογισμός, syllogismos, noun, "computation, calculation"
τέχνη, technē, noun, "art"

Charlton T. Lewis, Charles Short, A Latin Dictionary:
inductio, noun, "a leading or bringing into, introducing"

Arizona State University Library. Loeb Classical Library:
Aristotle, Posterior Analytics




"To say that it is somehow a natural process by means of which we arrive at first principles is to exploit Aristotle's generous conception of what is natural and to focus on just one aspect of it. This becomes particularly clear if we keep in mind that on Aristotle's view it also is the case that by nature we are meant to be virtuous and are thus constructed as to naturally be virtuous. Nevertheless, Aristotle also assumes that it takes a great deal of effort on our part to come to know the first principles in general (and thus to become wise), or even just the first principles in some domain. What is needed for this is a great deal of often highly specialized observation and of often highly technical reflections. But this should not obscure the fact that the insight, if it is an insight, does not derive its epistemic status from these observations and reflections which lead up to it. What makes it an insight is not the support it gets from observations or considerations, but that one finally sees in a way which fits how the features in question are related to each other and to other relevant features" (Michael Frede, "Aristotle's Rationalism," 172. Rationality in Greek Thought, 157-173).

"[Aristotle thinks] that organisms have to be understood teleologically, as naturally tending to achieve full development and perfection in their kind, unless handicapped or their development is thwarted. Since we naturally do have reason and since reason functions best, and serves its function best, if we do have the requisite knowledge, he assumes that we must be constructed in such a way as to be able to acquire the knowledge reason needs to function well. And he, too, thinks that he can explain this by assuming that there is a process which leads, on the basis of perception and memory, not only to our having concepts, but to our having concepts which are adequate to the way things essentially are, and which thus provide us with basic knowledge about things, but also with the ability to think and reason about things, properly speaking, instead of, for instance, just having impressions or even generalized impressions of things" (Michael Frede, "Introduction, 14. Rationality in Greek Thought, 1-28).

"On Aristotle's view it does not seem to suffice for thinking [as opposed to the ability we get from experience] that we have a notion of, say, a human being which allows us, by and large, to distinguish successfully between human beings and other things; the notion rather has to be based on a sufficient grasp of what it is to be a human being, of the crucial feature or features of human beings, and of how these features are related to each other and to a whole network of features. ... To grasp what it is to be a human being, on Aristotle's view, is more than just to grasp what human beings have in common; it is to grasp something which figures prominently in the explanation of human beings and their behavior" (Michael Frede, "Aristotle's Rationalism," 164. Rationality in Greek Thought, 157-173).

"However obscure, and in their interpretation controversial, the details of his account of how we acquire concepts may be, it is abundantly clear from [Posterior Analytics] 100a12-13 that Aristotle does not envisage that the concepts are acquired one by one in isolation. However we interpret the battle metaphor, it seems clear that he assumes that we begin with a tentative and unstable grasp of the different features, which constantly threatens to collapse until we get a firm grasp on some feature such that, given the way the features are interrelated, our grasp of the whole group solidifies and stabilizes. ... We do not come to acquire these concepts piecemeal, but by a process of mutual adjustment with other related concepts, as a result of which certain elementary relations between features in the end seem evident. ... [Aristotle] does not appeal to some mysterious power of the mind to see directly or intuit features or forms, but to some complex process in the course of which our notions again and again are readjusted until they finally fit into a coherent and appropriately structured system of notions and corresponding beliefs in terms of which we finally can make sense of what know from experience" (Michael Frede, "Aristotle's Rationalism," 171. Rationality in Greek Thought, 157-173).




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