"Four causes" refers to an influential principle in Aristotelian thought whereby explanations of change or movement are classified into four fundamental types of answer to the question "why?" Aristotle wrote that "we do not have knowledge of a thing until we have grasped its why, that is to say, its explanation." While there are cases where classifying an explanation is difficult, or in which classes of explanation might merge, Aristotle was convinced that his four classes of explanation provided an analytical scheme of general applicability.
Aitia, from Greek αἰτία was the word that Aristotle used to refer to the concept of explanation. Traditionally in academic philosophy it has been translated as cause, but this tradition uses the word 'cause' in a peculiar way that is obsolete, or highly specialized and technical in philosophy, not in its most usual current ordinary language usage. The translation of Aristotle's αἰτία that is nearest to current ordinary language is 'explanation'.
Aristotle held that there were four kinds of answers to 'why' questions (in Physics II, 3, and Metaphysics V, 2): In this article, the peculiar philosophical usage of the word 'cause' will be exercised, for tradition's sake, but the reader should not be misled by confusing this peculiar usage with current ordinary language.
- A change or movement's material explanation is the aspect of the change or movement which is determined by the material that composes the moving or changing things. For a table, that might be wood; for a statue, that might be bronze or marble.
- A change or movement's formal explanation is a change or movement caused by the arrangement, shape or appearance of the thing changing or moving. Aristotle says for example that the ratio 2:1, and number in general, is the explanation of the octave.
- A change or movement's efficient or moving explanation consists of things apart from the thing being changed or moved, which interact so as to be an agency within the change or movement. For example, the efficient explanation of a table is a carpenter, or a person working as one, and according to Aristotle the efficient explanation of a boy is a father.
- An event's final explanation is the end toward which it directs. That for the sake of which a thing is what it is. For a seed, it might be an adult plant. For a sailboat, it might be sailing. For a ball at the top of a ramp, it might be coming to rest at the bottom. For a person's action, it is the goal.
The four explanations are not mutually exclusive. For Aristotle, several answers to the question "why" have to be given to explain a phenomenon and especially the actual configuration of an object. For example, if asking why a table is such and such, a complete explanation, taking into account the four aitias, would sound like this: This table is solid and brown because it is made of wood (material explanation), it does not collapse because it has four legs of equal length (formal explanation), it is as such because a carpenter made it starting from a tree (efficient explanation), it has these dimensions because it is to be used by men and women (final explanation).
Meaning of "cause"
In his philosophical writings, Aristotle used the Greek word αἴτιον, aition, a neuter, singular form of an adjective. The Greek word had, perhaps originally, in a forensic context, a meaning of 'responsible', mostly but not always in a bad sense, of 'guilt' or 'blame'; alternatively it could mean 'to the credit of' something. The word developed other meanings, including its use in philosophy in a more abstract sense. In the present context, Aristotle used this word in the sense meaning an explanation that accounts for something; in this context, "x is the aition of y" means "x explains y".
The material explanation of an object is equivalent to the nature of the raw material out of which the object is composed. (The word "nature" for Aristotle applies to both its potential in the raw material and its ultimate finished form. In a sense this form already existed in the material. See Potentiality and actuality.)
Whereas modern physics looks to simple bodies, Aristotle's physics instead treated living things as exemplary. However, he felt that simple natural bodies such as earth, fire, air, and water also showed signs of having their own innate sources of motion, change, and rest. Fire, for example, carries things upwards, unless stopped from doing so. Things like beds and cloaks, formed by human artifice, have no innate tendency to become beds or cloaks.
In Aristotelian terminology, material is not the same as substance. Matter has parallels with substance in so far as primary matter serves as the substratum for simple bodies which are not substance: sand and rock (mostly earth), rivers and seas (mostly water), atmosphere and wind (mostly air and then mostly fire below the moon). Only individuals are said to be substance (subjects) in the primary sense. Secondary substance, in a different sense, also applies to man-made artifacts.
Formal explanation is a term describing the pattern or form which when present makes matter into a particular type of thing, which we recognize as being of that particular type.
By Aristotle's own account, this is a difficult and controversial concept. It is associated with theories of forms such as those of Aristotle's teacher, Plato, but in Aristotle's own account (see his Metaphysics), he takes into account many previous writers who had expressed opinions about forms and ideas, but he shows how his own views are different.
See also Platonic realism.
The "efficient explanation" of an object is equivalent to that which causes change and motion to start or stop (such as a painter painting a house) (see Aristotle, Physics II 3, 194b29). In many cases, this is simply the thing that brings something about. For example, in the case of a statue, it is the person chiseling away which transforms a block of marble into a statue.
Final explanation, or telos, is defined as the purpose, end, aim, or goal of something. Like the formal explanation, this is a controversial type of explanation in science (some of its aspects are used for instance in evolutionary biology, chaos theory, attractor and cybernetics. It is commonly claimed that Aristotle's conception of nature is teleological in the sense that Nature has goals apart from those that humans have. On the other hand, as will be discussed further below, it has also been claimed that Aristotle thought that a telos can be present without any form of deliberation, consciousness or intelligence. An example of a passage which is discussed in this context is from Physics II.8, where he writes
This is most obvious in the animals other than man: they make things neither by art nor after inquiry or deliberation. That is why people wonder whether it is by intelligence or by some other faculty that these creatures work, – spiders, ants, and the like... It is absurd to suppose that purpose is not present because we do not observe the agent deliberating. Art does not deliberate. If the ship-building art were in the wood, it would produce the same results by nature. If, therefore, purpose is present in art, it is present also in nature.
For example, according to Aristotle, a seed has the eventual adult plant as its final explanation (i.e., as its telos) if and only if the seed would become the adult plant under normal circumstances. In Physics II.9, Aristotle hazards a few arguments that a determination of the final explanation (cause) of a phenomenon is more important than the others. He argues that the final explanation (cause) is what brings it about, so for example "if one defines the operation of sawing as being a certain kind of dividing, then this cannot come about unless the saw has teeth of a certain kind; and these cannot be unless it is of iron." Moreover, the act of sawing has the purpose of cutting wood, as in contemporary cybernetics and perceptual control theory. According to Aristotle, once a final cause is in place, the material, efficient and formal explanations (causes) follow by necessity. However, he recommends that the student of nature determine the other explanations as well, and notes that not all phenomena have a final cause, e.g., chance events.
[E]verything that Nature makes is means to an end —Aristotle, On the parts of Animals, Book I, Part I
George Holmes Howison, in The Limits of Evolution, highlights "final causation" in presenting his theory of metaphysics, which he terms "personal idealism", and to which he invites not only man, but all (ideal) life; at p. 39:
Here, in seeing that Final Cause – causation at the call of self-posited aim or end – is the only full and genuine cause, we further see that Nature, the cosmic aggregate of phenomena and the cosmic bond of their law which in the mood of vague and inaccurate abstraction we call Force, is after all only an effect... Thus teleology, or the Reign of Final Cause, the reign of ideality, is not only an element in the notion of Evolution, but is the very vital cord in the notion. The conception of evolution is founded at last and essentially in the conception of Progress: but this conception has no meaning at all except in the light of a goal; there can be no goal unless there is a Beyond for everything actual; and there is no such Beyond except through a spontaneous ideal. The presupposition of Nature, as a system undergoing evolution, is therefore the causal activity of our Pure Ideals. These are our three organic and organizing conceptions called the True, the Beautiful, and the Good.
However, Edward Feser argues, in line with the Aristotelian and Aquinian tradition, that finality has been greatly misunderstood. Indeed, without finality, efficient causality becomes inexplicable. Finality thus understood is not purpose but that end towards which a thing is ordered. When a match is rubbed against the side of a matchbox, the effect is not the appearance of an elephant or the sounding of a drum, but fire. The effect is not arbitrary because the match is ordered towards the end of fire which is realized through efficient causes.
In their theoretical study of organism, more specifically propagating organisation of process, Kauffman et al. remark (p30)
Our language is teleological. We believe that autonomous agents constitute the minimal physical system to which teleological language rightly applies.
Perceptual control theory, developed by William Powers, offers a consistent and rigorous explanation of human behaviour in terms of intentional purpose with the control of sensory experience focused and controlled towards the attainment of a hierarchy of goals.
The four causes in modern science
Francis Bacon wrote in his Advancement of Learning (1605) that natural science "doth make inquiry, and take consideration of the same natures : but how? Only as to the material and efficient causes of them, and not as to the forms." According to the demands of Bacon, apart from the "laws of nature" themselves, the causes relevant to natural science are only efficient causes and material causes in terms of Aristotle's classification, or to use the formulation which became famous later, all nature visible to human science is matter and motion. Using the terminology of Aristotle, he divided knowledge into physics and metaphysics in The New Organon.
From the two kinds of axioms which have been spoken of arises a just division of philosophy and the sciences, taking the received terms (which come nearest to express the thing) in a sense agreeable to my own views. Thus, let the investigation of forms, which are (in the eye of reason at least, and in their essential law) eternal and immutable, constitute Metaphysics; and let the investigation of the efficient cause, and of matter, and of the latent process, and the latent configuration (all of which have reference to the common and ordinary course of nature, not to her eternal and fundamental laws) constitute Physics. And to these let there be subordinate two practical divisions: to Physics, Mechanics; to Metaphysics, what (in a purer sense of the word) I call Magic, on account of the broadness of the ways it moves in, and its greater command over nature. Francis Bacon The New Organon, Book II, Aphorism 9, 1620
Bacon's position became the standard one for modern science.
It has been controversially argued that explanations in terms of final causes remain common in modern science, including contemporary evolutionary biology, and that teleology is indispensable to biology in general for (among other reasons) the very concept of adaptation is teleological in nature. In an appreciation of Charles Darwin published in Nature in 1874, Asa Gray noted "Darwin's great service to Natural Science" lies in bringing back Teleology "so that, instead of Morphology versus Teleology, we shall have Morphology wedded to Teleology". Darwin quickly responded, "What you say about Teleology pleases me especially and I do not think anyone else has ever noticed the point." Francis Darwin and T. H. Huxley reiterate this sentiment. The latter wrote that "..the most remarkable service to the philosophy of Biology rendered by Mr. Darwin is the reconciliation of Teleology and Morphology, and the explanation of the facts of both, which his view offers." James G. Lennox states that Darwin uses the term 'Final Cause' consistently in his Species Notebook, Origin of Species and after.
Ernst Mayr states that "adaptedness... is a posteriori result rather than an a priori goal-seeking." Various commentators view the teleological phrases used in modern evolutionary biology as a type of shorthand. For example, S. H. P. Madrell writes that "the proper but cumbersome way of describing change by evolutionary adaptation [may be] substituted by shorter overtly teleological statements" for the sake of saving space, but that this "should not be taken to imply that evolution proceeds by anything other than from mutations arising by chance, with those that impart an advantage being retained by natural selection." However, Lennox states that in evolution as conceived by Darwin, it is true both that evolution is the result of mutations arising by chance and that evolution is teleological in nature.
Statements that a species does something "in order to" achieve survival are teleological. The validity or invalidity of such statements depends on the species and the intention of the writer as to the meaning of the phrase "in order to". Sometimes it is possible or useful to rewrite such sentences so as to avoid teleology. Some biology courses have incorporated exercises requiring students to rephrase such sentences so that they do not read teleologically. Nevertheless, biologists still frequently write in a way which can be read as implying teleology even if that is not the intention.
The four causes in technology by Heidegger
- causa materialis is the material or matter
- causa formalis is the form or shape the material or matter enters
- causa finalis is the end
- causa efficiens is the effect that is finished.
Upon explaining them in this formal state as well as with the example of a silver chalice, Heidegger raises the questions of why just these four causes, how was it determined that they exclusively go together, what exactly unifies them and what makes causa finalis and causa efficiens different. These are important questions to analyze and attempt to answer or else the definition of technology will remain obscure. He holds that the four causes are necessary to allow, for the material or matter which is not present, a path to become present. Heidegger argues that the ability to create a final product using these four steps is what unifies them as an exclusive group.
This group of causes brings Heidegger to poiesis: the bringing forth of something out of itself. He states that poiesis is the highest form of physis. Heidegger states that the four causes are at play in the bringing forth process of bursting open to the next artisan or creator. This process of bringing forth is revealing truth or aletheia, a key function of technology. Heidegger explains it as thus:
"Whoever builds a house or a ship or forges a sacrificial chalice reveals what is to be brought forth, according to the terms of the four modes of occasioning."
The word "reveals", instead of manufacturing, is important. Heidegger argues that manufacturing is not what brings forth a material but the actual revealing. Technology is the mode of revealing which gives truth, aletheia.
Highlighted is the issue of social and technological progress along with society with the four causes. One of his examples is the words through translation from the language of the Greeks, Romans and to today have created some issues with the definitions of these words. Most notably he emphasizes the need to clarify the difference between words that now have different meaning through these translations. In particular he uses the words responsible and indebted as they relate to the four causes and the creation process. Also used is the term techne which means technology now but it also was the word used for the “revealing which brings forth truth into the splendor of radiant appearance.” Within Greece, techne also meant art as it required the revealing and presenting the appearance of the work of art. The word aletheia was replaced by the Romans with veritas. Another issue arising with progress of technology and society is the techniques. Heidegger presents the argument that even though these Greek ideas work with techniques of handicraftsmen, they are essentially outdated with modern machine powered technology as they are based on modern physics. The problem is the modern physical theory of nature prepares for simple and modern technology. Heidegger uses examples like this to draw readers back to the four causes, proving that they remain relevant in today's world either directly with the newest products or their origination.
- Anthropic principle
- Convergent evolution
- Four discourses, by Jacques Lacan
- Proximate and ultimate causation
- The purpose of a system is what it does, Anthony Stafford Beer's POSIWID principle
- Tinbergen's four questions
- Aristotle, Physics 194 b17–20; see also: Posterior Analytics 71 b9–11; 94 a20.
- "Four Causes". Falcon, Andrea. Aristotle on Causality. Stanford Encyclopedia of Philosophy 2008.
- Lindberg, David. The Beginnings of Western Science (1992). p53
- Aristotle, "Book 5, section 1013a", Metaphysics, Translated by Hugh Tredennick Aristotle in 23 Volumes, Vols. 17, 18, Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1933, 1989; (hosted at perseus.tufts.edu.) Aristotle also discusses the four classes of explanation in his Physics, Book B, chapter 3.
- original text in Posterior Analytics 90a8, 94a20, original text in Met. 1013a on Perseus
- Liddell, H.G., Scott, R. (1843/2014). 
- Archetypes of Wisdom: An Introduction to Philosophy. By Douglas J. Soccio. Page 161.
- Physics 192b
- The Complete Works of Aristotle Vol. I. The Revised Oxford Translation, ed. Jonathan Barnes).
- This example is given by Aristotle in Parts of Animals I.1.
- Aristotle, Physics II.9. 200b4–7.
- Aristotle, Physics II.9.
- Physics II.5 where chance is opposed to nature, which he has already said acts for ends.
- Aquinas, Edward Feser.
- Kauffman, S., Logan, R. K., Este, R., Goebel, R., Hobill, D., & Shmulevich, I. (2008). Propagating organization: An enquiry. Biology & Philosophy, 23(1), 27-45.
- Lennox, James G. (1993). "Darwin was a Teleologist" Biology and Philosophy, 8, 409–21.
- Ayala, Francisco (1998). "Teleological explanations in evolutionary biology." Nature's purposes: Analyses of Function and Design in Biology. The MIT Press.
- Mayr, Ernst W. (1992). "The idea of teleology" Journal of the History of Ideas, 53, 117–135.
- Madrell SHP (1998) Why are there no insects in the open sea? The Journal of Experimental Biology 201:2461–2464.
- Heidegger, Martin. ed. Krell, D. F. (1977). The Question Concerning Technology. Basic Writings. New York: Harper & Row, Publishers. 289-290.
- Heidegger, Martin. ed. Krell, D. F. (1977). The Question Concerning Technology. Basic Writings. New York: Harper & Row, Publishers. 293.
- Heidegger, Martin. ed. Krell, D. F. (1977). The Question Concerning Technology. Basic Writings. New York: Harper & Row, Publishers. 294.
- Heidegger, Martin. ed. Krell, D. F. (1977). The Question Concerning Technology. Basic Writings. New York: Harper & Row, Publishers. 295.
- Heidegger, Martin. ed. Krell, D. F. (1977). The Question Concerning Technology. Basic Writings. New York: Harper & Row, Publishers. 315.
- Cohen, Marc S. "The Four Causes" (Lecture Notes) Accessed March 14, 2006.
- Falcon, Andrea. Aristotle on Causality (link to section labeled "Four Causes"). Stanford Encyclopedia of Philosophy 2008.
- Hennig, Boris. "The Four Causes." Journal of Philosophy 106(3), 2009, 137–60.
- Moravcsik, J.M. "Aitia as generative factor in Aristotle's philosophy." Dialogue, 14 : pp 622–638, 1975.
- English translation of Study on Phideas, by Pía Figueroa written with theme of Final Cause as per Aristotle.
- The Consequences of Ideas: Understanding the Concepts that Shaped Our World, By R. C. Sproul
- Aristotle on definition. By Marguerite Deslauriers, page 81
- Philosophy in the ancient world: an introduction. By James A. Arieti. p. 201.
- Doctrine of Being in the Aristotelian Metaphysics. By Joseph Owens and Etienne Gilson.
- Aitia as generative factor in Aristotle's philosophy*
- A Compass for the Imagination, by Harold C. Morris. Philosophy thesis elaborates on Aristotle's Theory of the Four Causes. Washington State University, 1981.