Metaphysics Book One, Chapter 3: Aristotle's approximately 4 causes

In Ch. 3 Aristotle continues his investigation of whether what is said about “wisdom” makes sense, and what it means. He notes that “we say we know each thing only when we think we recognize its first cause.” Note that he does not say that “we know each thing when we recognize its first cause,” but rather "we say we know each thing when we think we recognize its first cause." (What’s the difference? What difference does it make?)

As part of his investigation of what it means, whether it makes sense, to say that wisdom is knowledge of first causes and principles; and as part of his investigation of whether it makes sense to seek first causes and principles; Aristotle realizes he has to look into what people mean by saying that something is a cause (a “why,” a reason).

He notes in the first paragraph1 of Ch. 3 that causes are spoken of (literally, “said”) in 4 ways. In other words, when someone asks the question "Why?," Aristotle thinks, the person seems to be asking for one or more of four kinds of reply.
These are sometimes called “Aristotle’s 4 causes,” but be very aware of the following:

Aristotle does not say “There are only 4 causes” (only 4 reasons why something can happen or be as it is). He does not say that there are only 4 kinds of causes (4 kinds of reasons why something can happen or be as it is). What he says is that people speak of causes in 4 ways. Whether there are any other kinds of reasons for things is another matter. Aristotle finds that no one has coherently identified any other kinds, but he doesn’t say that no one ever will. (See also the last paragraph of Ch. 7 and the first sentence of Ch. 10. Aristotle mentions in Ch. 3 and Ch. 10 that he had already discussed the ways in which causes are spoken of, with the same result, in the Physics; see e.g. Book Two Ch. 3 and 7 of that work.)

What then are the “4 causes,” 4 ways in which people try to explain why things happen or are as they are?

Your translation gives them as follows:
  • "substance or essence";
  • "matter or substratum";
  • "source of the change";
  • "the purpose and good"
I will discuss them in a slightly different order than Aristotle, for better clarity (I hope). Be aware that first causes and principles will need to incorporate all of these kinds.

a. “matter or substratum,” hulē, sometimes called ‘material cause’ in the secondary literature: the constituent stuff of something. In the case of sensible objects, this can include what we would today call “matter”: what takes up space and has mass. But be careful: For Aristotle, it’s not only sensible objects that have constituent stuff. The “matter” (in Aristotle’s sense) of geometric shapes is lines and points (which he does not think are available to the senses).

(1) The matter of a wooden chair is wood; the chair is the way it it partly because it is made of wood. And on another level, we could ask why wood is as it is, and part of the answer to that would be that it’s made of carbon, hydrogen, and oxygen (among other things); these are chemically the “matter” of wood. So if someone asked why a given chair is the way it is, at least part of the answer is what it's made of. (Why is the chair flammable?  - Because it is made of wood.) Be aware that we can seek even more primary material causes; we can explain why wood is flammable, what the chemical composition of wood is, and so on. Simply to say that the chair is made of wood is to give a cause of why it is the way it is, but that is not to give a first cause.

(2) A circle is the set of all points equidistant from a given point. Thus some of why a circle is the way it is comes from the points it’s made of. This is perhaps easier to see if we say that a given circle is composed of a certain set of specific points. Thus the matter of the circle is its points. Of course, since a circle is an infinite set of points and a line is an infinite set of points, in geometry, other causes must be involved if we are to explain how a line and a circle are different; and how one circle differs from another. For that, we must turn to the other kinds of cause; see especially c. below.

(3) In Physics Book Two Ch. 3 Aristotle gives some more examples that may be helpful. One is that letters are that out of which syllables are composed.

(4) Another is that the premisses of an argument are the "matter" of the argument, and are that from which the conclusion of the argument is formed.

b. “source of change,” sometimes called “moving cause” or “efficient cause” in the secondary literature: What sets off a change. (Obviously things that are not the results of changes or motions won’t have this kind of cause.)

(1) If something burned, catching on fire was the efficient cause of the change.

(2) If a home was built, the actions of the builders were the source of the change.

(3) An ideal circle may not have a moving cause, but a drawn circle has the person who drew it, or his/her actions, as moving cause.

(4) In the Physics, Aristotle notes that if someone gave you advice and that advice motivated you to do something, then one could see the advice-giver as a source of your action. Or perhaps your understanding of the advice (which may be different from the intent of the advice) was the cause of your action. Again, one can seek causes of this kind on various levels: perhaps the source of your action was the advice, and perhaps the source of the giving of advice was that the advice-giver had been motivated to be generous, etc.

c. “substance, essence,”2  to ti ēn einai, what it is to be [something or some way]; Aristotle sometimes uses the expressions logos  (account) or 'definition' or 'formula' or 'form'; the secondary literature often refers to this as “formal cause.” ‘What it is to be’ is probably the most helpful way to think about this.

If something has a particular form, part of what makes it the kind of thing it is, is that form.

This "form" can be the characteristics that distinguish or define a species, or the characteristics that distinguish one individual from another. One example Aristotle often gives (e.g. at Physics Book Two Ch. 3) is that of accounting for the difference between a lump of bronze and a bronze statue. The same piece of bronze (the "matter," in sense a. above) can take either form. For a given piece of bronze, part of what explains what it is is its physical makeup, and part is the form it is currently taking. That of course also has to do with what forces acted on it (the second kind of cause), but Aristotle’s point is that the question of what forces or actions were involved, and what form the bronze wound up in, are two different questions. Each is part of the answer to “Why is the bronze this way?”

(1) Aristotle says in Physics Book Two Ch. 3 that the relation 2:1 is the form of the octave: it is the form that any ratio of string lengths (on a lyre or similar instrument) must have in order to produce notes one octave apart. Thus the nature of number is a further cause of this type.

(2) The circle and the line are both forms of infinite sets of points; what it is to be a circle (definition of a circle) is to be the set of all points equidistant from a given point, and what it is to be a line is to be the set of all points determined by two given points (the set of all points connecting two given points and extending beyond those points in such a way that a segment connecting any two points will also be on the same line).

(3) If you make a chair and a table out of the same wood - say, for purposes of argument, that you had a table and when part of it broke you made the rest of it into a chair, so that the matter of the chair was (part of) the exact same matter as the table. Why the chair exists and is as it is includes that it is made out of this wood (matter); that you made it when the table broke (you were the moving cause of the chair coming to be); and that it has the form of a chair. Put another way, the difference between the table and the chair is that they have different forms.

d. “that for the sake of which,” the end or goal or purpose or good; often the secondary literature refers to this as “final cause.” (That term can be confusing - do not confuse final cause with first cause. Here, ‘first’ means ‘ultimate, most fundamental.’ ‘Final’ means ‘oriented toward a goal or end.’ Don’t blame Aristotle for this confusing translation!)

“That for the sake of which” is a cause in the sense that it refers to why something happened or was done. Perhaps some events and conditions do not have causes of this type. (Aristotle doesn’t say that all events and conditions have this kind of cause, and he doesn’t say that they don’t.)

 (1) This is the kind of cause that Socrates refers to at Phaedo 98-993 when he speaks of the “real cause” of his being in jail: he acted for the sake of what he thought was right or best, and the plaintiffs acted for the sake of what they thought was right of best. The actions, and the people who performed them, would have been “moving causes,” but the reasons why they were done (the sake of what one thinks is right or best) would be “that for the sake of which”-type causes.
 (2) Aristotle sometimes mentions this kind of cause in a way that suggests that choice may not be at work; he uses the term “for the sake of which” very broadly. He says that acorns are for the sake of oaks, that oaks are the “final cause” of acorns. Thus he may be suggesting that “for the sake of which” can connote directions or tendencies.

The question arises, what does this have to do with "first" causes, ultimate reasons and sources for things?

We might look at it thus: In each of these 4 ways, we can ask "why?" on a deeper level or a shalllower level. First causes, if they exist, would be at the deepest level.

So, take "matter"-type causes for example.

The question "Why is this piece of toast the way it is?" can be answered at a surface level with something like "Because it is made of bread."

But we can go deeper along the lines of the "matter"-type cause; we can ask about the "matter" of bread, the constitution of bread (wheat, water, eggs, etc.).

And we can go deeper than that: wheat is the way it is, in part, because it is made of carbon, hydrogen, and oxygen, etc. Carbon is the way it is because of, say, its composition of subatomic particles, etc.

If there was a "bottom" or most fundamental level, and if we could we could learn what is at that very "bottom" level, i.e. learn the ultimate constituents of what is, then it seems we would have a "first cause" of the "matter" type. We'd be able to say why everything is, in terms of what it's made of.

But from what was said in Book One Chapter 2, it seems that all 4 kinds of cause have to fit together, or unite, at the "first cause" level. Otherwise, if we found what we thought were "first causes" of all four types, we could still ask why they went together. That is, we could still ask for a deeper cause that incorporated all four types. We wouldn't have first causes (ultimate reasons) until we knew that.

The question then arises, what is the relevance of all this?

Aristotle uses this "4 ways causes are spoken of" schema to analyze what he thinks his predecessors did in so far as they were seeking causes. (He does not say that all they did was seek causes.) It helps to bring out what he thinks will need to be done if we are to work out the consequences of the hypothesis that the search for wisdom is or involves the search for must fundamental causes and principles; and if the hypothesis does seem sound, this will tell us something about where we’ll need to look in order to seek wisdom.

But the “approximately 4 kinds of cause” framework is also useful today. Recent work in the social sciences, and to a lesser extent in the natural sciences, has suggested that the Humean model of causality, which focuses on moving causes and to some extent material causes, simply is not enough by itself.

1. In quoting and in referring to Aristotle's text I am using the Ross translation, available here, among other places: Metaphysics  ; Physics  . Thus when I mention specific paragraphs, these correspond to paragraphs in that translation. (back)

2. The word 'substance' in your translation translates ousia, which is  a participle of the verb 'to be.' Thus it can be translated as 'being' and can mean a distinct independent thing (a thing as something in its own right and not as a part or aspect of another thing). Each distinct thing is distinguished from other things by its characteristics; the defining characteristics are what make it the distinct thing that it is. That's what Aristotle is focusing on here, so "defining characteristic" or "what it is to be [some particular thing]" seems to be the clearest way of expressing what he's talking about. 'Essence' in your translation translates to ti ēn einai, literally "what it is to be." (back)

3. The numbers in the reference to Plato are Stephanus numbers, not page numbers of a particular translation. (back)

Questions, comments?
Contact me at rcherubi(at)gmu(dot)edu.

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Metaphysics Book One, Chapter 3: Aristotle's approximately 4 causes by Rose Cherubin is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.