What Sensible Substances Are

To call something a substance is attribute a kind of existence to to it. Aristotle, in Book II of the Physics, thinks that within in each sensible substance is a ⊕ The noun nature is from the Latin natura. This was a standard translation of the Greek noun φύσις.

The Latin noun physica transliterates the substantive use (the use as a noun) of the Greek adjective φυσική.

In the phrase 'inquiry into nature,' the Greek for 'inquiry' is ἱστορία. This Greek noun transliterates as historia.

The title of Herodotus's Histories is Ἱστορίαι.

"This is the display of the inquiry (ἱστορίης) of Herodotus of Halicarnassus, so that things done by man not be forgotten in time, and that great and marvelous deeds, some displayed by the Hellenes, some by the barbarians, not lose their glory, including among others what was the cause of their waging war on each other" (Histories I.1).

The term 'natural history' (as in the name of the AMNH in NYC) preserves some of the ancient sense of 'inquiry into nature' (ἱστορία περὶ φύσεως). This is due in part to the importance in the history of science of Aristotle's Περὶ Τὰ Ζῷα Ἱστορίαι ("Inquiries about Animals"), which is commonly called by its Latin title Historia Animālium or English translation History of Animals.


Book II of the Physics:

Chapter 1. The nature in a thing
Chapter 2. The physicist
Chapter 3. Causes.
Chapter 4. Outcomes by luck and by accident
Chapter 5. Luck
Chapter 6. Accident
Chapter 7. Summary thus far
Chapter 8. The for something
Chapter 9. Necessity


"Of things that are, some are by nature, some because of other causes. By nature are the animals and their parts, and the plants and the simple bodies (earth, fire, air, water)—for we say these and the like exist by nature. They seem distinguishable from things not united by nature. Each of the beings that exist by nature has within itself a starting-point of change and staying unchanged" (Physics II.1.192b).

"For nature is a starting-point and cause of being moved and of being at rest in that to which it belongs primarily according to itself and not accidentally" (Physics II.1.192b).

"Nature is said to be the shape and form according to the account [of what the object is]" (Physics II.1.193a).

"What is potentially flesh or bone has not yet its own nature, and does not exist by nature, until it receives the form according to the account (τὸ εἶδος τὸ κατὰ τὸν λόγον), which we say in defining what flesh or bone is. ... So the nature of things having a starting point of change is the shape or form, which is not separable except according to the account . ... And this is more [what] nature [is] than the material [is what nature is]" (Physics II.1.193b).

"separate" (χωριστὸν)

"To what point should the physicist know the form and the what it is (τὸ εἶδος καὶ τὸ τί ἐστιν)? ... [To the point of knowing] what is separable in form but in matter (χωριστὰ μὲν εἴδει, ἐν ὕλῃ δέ) ... What is separable [without qualification], and how things are with it, is the work of first philosophy to determine" (Physics II.2.194b). "nature" (φύσις) and that this nature is a "starting point of change and staying unchanged" (Physics II.1.192b).

We can get some insight into what Aristotle is thinking by recalling something Socrates says in the Protagoras. In his discussion of whether pleasure can overcome knowledge, Socrates thinks the dialectic has shown that this sort of behavior is not "in human nature."

"Then [given what has been agreed,] no one willingly goes after bad or what he thinks to be bad; it is not in human nature (ἐν ἀνθρώπου φύσει), apparently, to do so—to wish to go after what one thinks is bad in preference to the good; and when compelled to choose one of two bads, nobody will choose the greater when he may choose the lesser" (Protagoras 358c).

Aristotle takes human beings to be sensible substances and thinks, like Socrates, that human nature causes them to behave in the specific ways human beings do. Aristotle wants to know what a nature is in the existence of a sensible substance so that it is such a cause.

Natures are Forms in Matter

⊕

Theseus slays the Minotaur.

In the Phaedo, Echecrates asks why Socrates spent so much time in jail after his conviction. Phaedo answers that the execution was delayed because the ship of Theseus had not returned from Delos. Athens was to be kept pure until the ship returned, so no executions were carried out.

Delos (Δήλος) is an island in the Aegean Sea. To understand the conclusion Aristotle draws, it helps to think about the prior history.

The inquirers into nature after Parmenides eliminate the objects we traditionally think exist. Democritus explains them away as a product of a "bastard" way of thinking about atoms in the void. In this thinking, what we traditionally think are objects are illusions our minds create. Atoms together in the void appear to us as objects we wrongly take to be real.

Against this Presocratic tradition, Aristotle follows the general line of thought in the Timaeus that these objects are real and that forms play a role in the explanation of their existence.

Aristotle thinks that the natures of sensible substances are forms, but he understands the existence of these forms in a new way. He does not think that they are separate as Plato seems to have thought. He says that they are "in matter" and "separate in account."

Now we need to know what Aristotle means by "in matter" and "separate in account."

The Ship of Thesesus

⊕
"The ship on which Theseus sailed with the youths and returned in safety, the thirty-oared galley, was preserved by the Athenians down to the time of Demetrius Phalereus [fourth to third century BCE]. They took away the old timbers from time to time, and put new and sound ones in their places, so that the vessel became a standing illustration for the philosophers in the mooted question of growth, some declaring that the vessel remained the same, others that it was not the same" (Plutarch, Life of Theseus 23 (in Parallel Lives (a set of biographies of famous men))). We can engage in a thought experiment to help us get this knowledge.

The subject of this experiment is the ship of Theseus. The ship was known to be ancient in Socrates' day and to have been repaired many times. The question is what in the ship persists when it continues to exist as itself over the years through its many repairs.

The material from which the ship is built does not seem to be the answer. After the boards and other materials were replaced, the repaired ship is still the ship of Theseus.

It seems instead that the unrepaired and repaired ship are the same ship if the material has the same organization. The original organization must be present for the ship to exist.

Aristotle has this sort of view about sensible substances. Their nature is an organization of material so that there is is something that behaves as members of the kind behave.

Aristotle's Theory of Forms

Now we can see how the forms of natural bodies are "in matter" and "separate in account."

The form of a ship is the particular organization of the pieces of wood and other materials so that there exists a ship of a certain kind. Removing this organization from these materials causes the organization to go out of existence because it destroys the ship by taking it apart. So, in the absence of this organization, there is no ship of Theseus. There is only a pile of pieces of wood and other materials we might use to try to put the ship back together.

There is a way, though, Aristotle thinks, that the form is separate from the matter.

The ship of Thesus is a galley, and a ship of this form is a ship that functions in a certain way. It is a ship propelled primarily by oars, has a shallow draft, and has low freeboard. This description makes no mention of the pieces of wood and other things we use to build galleys. This, Aristotle thinks, makes the form of the ship separate from the matter in account.

When Aristotle says that the form is "in matter" and "separate in account," he is giving what he takes to be the truth in Plato's conception the existence the forms of natural bodies. Aristotle thinks Plato was right that the forms of natural bodies are separate, but he was wrong to think they are separate without qualification. As Aristotle understands the forms of natural bodies, they exist in matter and can exist separately from it only "in account."

To see the difference from Plato's view, it helps to remember the picture in the Timaeus. The divine craftsman constructs the cosmos by using the form of a living creature as his model (Timaeus 37c). This form contains the forms of the other living creatures (Timaeus 39e). The maker constructs the "heavenly race of gods" and tasks them to construct the living creatures subject to death by imitating what he himself did to construct these gods (Timaeus 41c).

Whereas for Plato the forms exist apart and prior to the "living creatures," Aristotle makes the forms of each of the natural bodies numerically distinct but identical in account.

"Your matter and form and moving cause are different from mine, but they are the same in their general account [because we are both human beings]" (Metaphysics XII.5.1071a).

Each form is a numerically distinct organization of matter. These forms are not apart and prior. They are not universal patterns the divine maker uses in the construction of the cosmos.

⊕ "Don’t be surprised, Socrates, if in many cases on numerous subjects regarding the gods and the generation of the universe, we prove unable to furnish accounts entirely and in every way consistent with themselves and exact. Indeed if we can offer an account that is as likely as any other, we should be content, remembering that I who speak, and you who judge, possess a human nature and so it becomes us to allow the likely story (εἰκότα μῦθον) about these matters and forbear to search beyond it" (Timaeus 29c). This is one part of Aristotle's attempt to correct the picture of reality in the Timaeus, which Timaeus tells Socrates he should not take what he is saying as more than a "likely story."

Thinking More about Aristotle

In addition to his new way of thinking about the forms of sensible substances, Aristotle also reimagines the teleology in the Timaeus. In the Timaeus, the model for the telelogy is the craftsman. As we will see, Aristotle rejects the craftsman but keeps the teleology.

Perseus Digital Library

Aristotle, Metaphysics
A Dictionary of Greek and Roman Antiquities: THEO´RIS (θεωρίς), THEO´RI (θεωροί)

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

θεωρία, theōria, noun, "a sending of" θεωροί or "state-ambassadors" to the oracles or games,
or, collectively, the θεωροί themselves, "embassy, mission"
θεωρίς, theōris, noun, "sacred ship, which carried the θεωροί to their destination"
θεωρός, theōros, noun, "envoy," ("spectator" in the sense of "overseer")

κόσμος, cosmos, noun, "order"
παράδειγμα, paradeigma, noun, "paradigm"

The θεωροί ("overseers") were sacred ambassadors sent on special missions (θεωρίαι) to perform some religious duty for the state, to consult an oracle, or to represent the state at some religious festival. In Athens, it seems that three ships carried the θεωροί: the Delia (Δηλία), the Salaminia (Σαλαμινία), and the Paralus (Πάραλος).) The Greeks thought that the Δηλία was very old and that it had once taken Theseus to Crete.

Arizona State University Library. Loeb Classical Library.
Aristotle, Physics

"Aristotle thinks that the capacity of an object to behave in this characteristic way [that characterizes it as a member of a natural kind] depends on its organization, structure, and disposition, indeed, he thinks that it is just this disposition or organization that enables the object to behave the way it does. Now, for Aristotle, the form is this disposition or organization, while the matter is what is thus disposed or organized. How could the form, so construed, satisfy the requirements laid down for being a substance? An important requirement was that the substance was to explain why, despite all the changes an object had undergone, it still is the same object. How the form could satisfy this requirement, we can see from the ancient example, expanded by Hobbes, of Theseus's ships, Theoris, which for centuries has been sent to Delos on an annual pilgrimage and whose return Socrates, in the Phaedo, must await before he may drink the poison. Over the years, the ship is repaired, plank by plank, always, however, according to the original plan. Now, let us suppose there is a shipwright who keeps the old planks. After all the old planks have been replaced in Theoris, he puts them together again according to the original plan and thus has a second ship. It seems obvious to me that this ship, even though it is constructed from all the old planks and according to the original plan, is not the old ship, Theoris, but a new ship; the ship constructed from the new planks is, in fact, the old ship. ... What makes for the identity of the repaired ship with the original ship is obviously a certain continuity. This is not the continuity of matter, or of properties, but the continuity of the organization of changing matter, an organization which enables the object to function as a ship, to exhibit the behavior of a ship" (Michael Frede, "Individuals in Aristotle," 66. Essays in Ancient Philosophy, 49-71).