Notes on Physics Epsilon (E)



I. Kinds of change, or respects in which a thing changes (or is said to change):
A. "accidental": When we say that "the musical [thing]" is walking, the "musical [thing]" would be changing accidentally; as Aristotle says, that which is walking is something of which musicality is an attribute. Recall that in Greek, the expressions for 'the musical', 'the musical thing', and 'the musical person' (e.g., a musician or a musically talented person) were the same. To say "to mousikon badizei", "the musical is walking", might sound in Greek like a claim that the quality of being musical was doing something or undergoing some change, when in fact it is the person who "has" the quality who is doing the walking, and whose body is moving. The musicality is not walking in or of itself; that is, the musicality and all of the other attributes of the person (hair color, age, food preferences, etc.) are of course brought along in the walking, but only because the person whose attributes they are is walking. Musicality does not walk by itself. For this reason, Aristotle will not discuss "accidental" change: it exists in all things (that undergo changes), and in calling it "accidental" we are saying that it is only happening because of non-accidental change, or that it wouldn't happen without non-accidental change; so in order to try toget a handle on change, we need to look at the main, non-accidental changes and the specific ways in which they do and do not occur.


B. A thing is said to change "simply" when some part in it changes. For example, if you have an eye infection and it heals, we might say that your eye has healed, but we could also say that your body has healed (in that the eye is considered to be part of the body), or that you have healed (in that your eye is considered to be part of "you"). Thus when the eye infection healed, you, or your body, would be said to have changed "simply". This is a "non-accidental" kind of change.


C. Sometimes a thing is said to change "by being primarily itself in motion". In this case it would not be in motion "accidentally" nor in motion in the sense that only something (i.e. not all) in it is in motion. In this case, the thing as a whole would be said to be essentially movable. For example, if you threw a rock, the entire rock would be said to be primarily itself in motion. If all the liquid in a glass were to change from red to blue, the liquid would be considered to be primarily itself in motion. That is, it would not be in motion only as a part of something else, nor in motion only in the sense that a part of it is in motion, nor only in motion in the sense of being brought along with something else that is moving.

[Note that C. does not mention ALL change, but only motion.]


Non-accidental change does not exist in all things, but only in contraries, in intermediates, and in contradictories. that is, if a thing changes, it becomes in some way not exactly the way it was before the change: it, or some aspect of it, becomes contrary or contradictory to the way it was before the change. If the thing is said to change so as to be in some way contrary to the way it was, it will go through some intermediary state between the two states that are said to be contraries. ("Contraries", in this context, would be the things within each genus (kind) that are most different from each other: large and small (or largeness and smallness) are contraries with respect to size; dark and light are contraries in terms of illumination; red and green, or blue and yellow, or black and white, are contraries with respect to color; and so on. Contraries are polar opposites that have intermediates between them: medium is between large and small; dim is between dark and light; and so on. "Contradictories" in this context would be opposites that are incompatible with each other - we take it as axiomatic that a thing cannot exhibit two contradictory aspects in the same way in the same respect at the same time - and that have no intermediate between them. Green and not-green are contradictories, as are large and not-large, etc. That is, if a thing goes from being green to being not-green (to not being green), it does not, we say, go through an intermediate stage between being green and being not-green. Thus some changes will be both changes between contraries and changes between contradictories, depending on what aspect of them we are looking at. If an apple goes from being green to being red, we may describe this as a change from being green to being red, and bring out the fact that it goes through intermediate stages between green and red (greenish-pink, light pink, dark pink, etc.). Or we could say that the apple went from being green to not being green, and bring out the aspect of the opposition that is binary or exclusive, i.e. the aspect that has no "in-between".)


-----Why is Aristotle going through all of this? One reason is that he is trying to delineate the essential aspects of certain kinds of changes that he is going to focus on later, and in order to do that he must distinguish these kinds of changes clearly from other kinds that might be or seem to be like the ones he wants to talk about. At the same time, he seems to want to try to describe these kinds of changes in a way that will make sense and that will also allow for at least the possibility that there could be knowledge about the things studied in physics. Or at least, he seems to be trying to see whether or to what extent such a description can be given. If we are right to suspect (Book A) that knowledge in a particular area or field involves an understanding of the "why" of things in that field, then for there to be knowledge in physics, we would have to be able to grasp the causes (why's) and principles (sources) of things that move and change. Thus one thing Aristotle will be concerned with is whether those things that move and change (or that are taken to move or change) can be described in a coherent and consistent way, so that causes and principles can be sought. In particular, he will try to see whether (or under what conditions) a coherent and consistent account of motion and change is possible: an account that does not contradict itself, is not circular, does not involve infinite regresses (which effectively preclude identification of reasons and sources for things), does not involve assumptions we can show no reason for regarding as axioms, and so on.

II. (225a-b) There can be just 3 kinds of change. That is, since every change is supposed to be a change from something (or from being one thing, or one way) to something else (or to being another thing, or another way), there would appear to be 4 possible alternatives for that which is changing. Of these 4, only 3 will be possible - or, perhaps, conceivable. The 3 possible kinds are:
A. A change from a subject (hupokeimenon) to a subject (hupokeimenon).
This sort of change must be a motion. The hupokeimena (plural of hupokeimenon) of this motion must be contraries or intermediates.

The idea seems to be this: A hupokeimenon is literally "that which is laid down", "that which has been [placed as] underlying". If something that has been laid down as existing is taken to continue to exist although some aspect of it is taken to become different, and if nothing underlying is taken to go out of existence, what is taken to have gone on is what is called a motion. Or, put another way, if a change is taken to occur such that something that is said to undergo the change persists through the change, that change is called a motion. The two poles of the motion (what the thing is changing from and what it's changing to) will be understood as contraries or intermediates, not as contradictories, for changes between contradictories are seen as generations and destructions, i.e. as involving the unqualified (absolute) or qualified (conditional) appearance or disappearance of a hupokeimenon. (See the note below concerning the possibility that a given event could be understood as a motion from one perspective and a generation or destruction from another.)

Examples. If a piece of white bread gets toasted, it will go from being white to being brown or black in color. This is a motion with respect to quality; motions with respect to quality are called alterations.
If the bread shrinks in size when it gets toasted, that change will be a motion with respect to quantity, specifically a decrease (increase is of course the other motion with respect to quantity).
When you put the bread into the toaster, the bread has changed place. Motions with respect to place are called locomotions.


B. A change from a non-hupokeimenon to a hupokeimenon with respect to contradiction is a generation (a coming-to-be). It is an unqualified coming-to-be if the change is unqualified, and a qualified coming-to-be if the change is qualified.
Examples. A change from not-blue to blue (from a not-blue thing to a blue thing, i.e. from a thing being not blue to the thing being blue) is a qualified generation (qualified coming-to-be): a thing that exists, whose qualities included not being blue (or which was a "not-blue" kind of thing), became (came to be) a thing that is a blue thing. (Again, see the note below concerning the possibility that this kind of generation might be the sort of event that can be seen from another perspective as a motion.)
To change from [an] unqualified not-being (me on) to [a] substance (ousia, being) would be an unqualified generation (unqualified coming-to-be): something that did not exist in any way before is said to come to be. ("Unqualified not-being" is not-being-at-all. It seems possible that in some contexts in physics, a certain thing might be said not to exist at all, whereas in other contexts in physics that thing might be said not-to-exist in a qualified way. For example, putting aside the question of exactly when life begins, it will generally be agreed that a child does not exist before its parents are born. Certainly the child's body will not be taken to exist before its parents are born. However, the child or its body are not taken to have come to be from nothing at all. Rather, we say, the cells that make up the child's body at birth come from (develop as) cells contributed by each of its parents, cells that came to be from other cells in the parents' bodies, etc.)
Unqualified not-being, or an unqualified non-being, cannot be at rest or in motion: there's no hupokeimenon to move or rest. Generation and destruction of the unqualified sort therefore cannot also be motions. (Aristotle does not discuss whether there can be any change in "nature" which is only an unqualified generation or destruction, and not in any way or context a qualified one. That is, he does not discuss whether anything in nature must be said to come to be from nothing or to disappear into nothing. If there are to be causes and principles in physics, there had better not be anything that comes to be from nothing - for then it has no source or cause - or that disappears into nothing: we'd never be able to tell whether a given change or motion was an alteration, say, or a complete disappearance of one thing and an instantaneous appearance on the scene of another thing.(Aristotle does not say all of that explicitly. But we may note that the rest of the Physics is concerned overwhelmingly with motion, not unqualified generation and destruction. More than just coincidence? Or, less?)


C. A change from a hupokeimenon to a non-hupokeimenon is a destruction. It is an unqualified destruction if it is a change from a substance (ousia, being) to [a] non-being (me einai, literally "not-to-be"), and a qualified destruction if it is from a qualified being to the opposed negative. (In other words, the reverse of generation.)


Note. It seems possible that an event that would be called a qualified generation or a qualified destruction in one context in could be called a motion in another context. For example, if you dye a white shirt blue, the shirt will on the one hand be said to "move" from being white to being blue. The fabric continues to exist and continues to function as a shirt; it has altered in color. On the other hand, especially in Greek but also in English, one might also say that the shirt "came to be blue" (the word for "coming-to-be" is the same as the word for "generation", namely 'genesis'), or that blue color "came to be" present in the shirt, or that the white color in the shirt is "gone" or has "ceased to be" in the shirt; etc. In fact, one could even say that a white thing has ceased to be, in a qualified sense: the shirt has ceased to be a white thing; a white shirt no longer exists as a white shirt. A (this) blue shirt did not used to exist, in the sense that the shirt did not exist as a blue shirt; but now a blue shirt does exist.
The classification Aristotle is making here is not an idle one. It points up the fact that processes are understood differently within different contexts, and in physics we will need to be able to identify how something is being taken in order to be able to account for what is going on. Also, it is important to note that what seems from one perspective to be something coming into existence or going out of existence might seem from another perspective to be a case of something persisting but undergoing a motion of some sort. If, as noted above, we are hoping that there are causes and principles at work in physics, we would have to give up this hope if some things could only be understood as cases of something going into existence (in some way, or entirely) or out of existence. If causes and principles might not be at work in some events, we could not tell when if at all they were at work. But we will not have to worry about this if all apparent generations and destructions treated by physics were also motions. We'd still have conceptual problems in understanding how to make sense of claims about going into and out of existence, but there would be (possibly) viable alternative ways of understanding such claims within physics.



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