Commentary Aristotle Physics
460. Then, at “the extension between” (211b14), he takes up the question of space.
First, he sets down why space seems to be place;
second, he shows that it is not place, at “but there is no such extension” (211b18; [461]).
He first says that, frequently, a body contained by place and distinct from it is changed from one place to another, and any number of bodies can succeed into its original place (but always in such a way that the container remains immobile) in the way that water goes out of a vessel.
For this reason, it seems that place is some middle space between the boundaries of the containing body, as though there were something there besides the body moved from one place to another. For if nothing were there besides the contained body, it would follow either that place is not distinct from the thing in place or that what exists within the confines of the container’s boundaries cannot be place.
Now, just as place must be something over and above the contained body, so it must be something other than the containing body, due to the fact that place remains immobile, while the containing body and everything in it can be changed about. But, in addition to the containing body and the contained body, there is nothing present except the dimensions of space, which exist in no body. Consequently, because place is immobile, it seems that space is place.
461. Then, at “but there is no such extension” (211b18), he shows that space is not place by two arguments.
As to the first of these, he states that it is not true that there is anything within the confines of the containing body other than the contained body that is transferred from place to place. Rather, within the confines of the containing body, there happens a body of some kind, having, nevertheless, the following two characteristics: that it be a mobile body, and be naturally apt to touch the containing body. But, if, in addition to the dimensions of the contained body, there were present a space that always remained in the same place, the embarrassing conclusion would follow that there would be infinite places together. The reason is that water and air have their own dimensions, and so does each body, and each part of a body. Now, all these parts will do the same thing in the whole body that the whole water does in a vessel.
According to those who hold the opinion that space is place, when the entire water is in the vessel, there are present, in addition to the dimensions of the water, also other dimensions of space.
Now, every part of a whole is contained by the whole as a thing in place is contained by a vessel: the only difference being that the part is not separated from the whole, but the thing in a place is separated from place.
If, therefore, a part be actually separated within the whole, it will follow that, in addition to the dimensions of the part, also other dimensions of the containing whole will be present. But it cannot be said that such division would make new dimensions to exist, for division does not cause dimension; rather, it divides dimension already existing.
Therefore, before that part was divided in the whole, there were present other proper dimensions of the part in addition to the whole’s dimensions that also penetrate that part. Now, there will be as many distinct sets of dimensions, some of which interpenetrate others, as there are parts obtainable by division of the whole, which parts are so divided that one contains another.
But it is possible in a continuous whole to obtain infinitely many parts that contain other parts, because a continuum can be divided to infinity. Consequently, we should have infinite dimensions mutually penetrating themselves. If, therefore, the containing body’s dimensions, penetrating the thing in place, are place, it follows that there are infinite places together—which is impossible.
462. Then, at “at the same time” (211b23), he gives a second reason, which is the following. If the dimensions of the space that is between the boundaries of the containing body are place, it follows that place can be transported. For it is clear that, when a body is transported, such as a jug, the space within the jug is transported, since that space can never be except where the jug is. Now, whatever is transported to another place is penetrated (according to those who hold the doctrine of space as place) by the dimensions of the space into which it is transported. Therefore, it follows that other dimensions enter the dimensions of the jug’s space; consequently, there would be another place of place, and many places would be existing together.
463. This unacceptable consequence arises from positing one place for the contained body (for example, the water) and another place for the vessel (for example, the jug). For according to the opinion we are discussing, the place of the water is the space within the boundaries of the jug, while the place of the whole jug is the space within the boundaries of the body containing the jug. We, however, do not assign a special place for the part in which the part moves, as distinct from the whole, when the entire vessel is transported (by part, he means the body contained in the vessel, as the water contained in the jug), for according to Aristotle, the water is moved per accidens when the vessel is transported, and it changes place only inasmuch as the jug changes its place.
Hence, it is not necessary that the place into which the transfer is made be the place of the part per se, but only inasmuch as it becomes the place of the jug. But, according to those who hold the opinion about space as place, it follows that the new place would belong per se both to water and to the jug. Likewise, space would be transported and would have a place per se, and not only per accidens.
Now, although the containing body is sometimes moved, it does not follow according to the opinion of Aristotle that the place is moved, or that there is a place of a place. For it does indeed happen that a containing body, in which something is contained, is sometimes moved, as are air or water or certain parts of the water. For example, if a boat is in a river, the parts of the water that surround the boat from below are in motion, but the boat’s place is not moved. Hence, he adds, not in that place in which they come to be; that is, that in which things come to be as in a place is not moved.
How this is true he makes clear by adding, which is a part of the place that is the place of the whole heavens. For although this container be moved inasmuch as it is this body, yet in regard to its relation to the whole body of the heavens, it is not moved: the body that succeeds it has the same order or position in relation to the whole heavens as had the body that previously flowed on. This, therefore, is what he says: although the water or the air be moved, the place is not, considered precisely as a certain part of the place of the whole heavens and as having a definite position in the universe.
464. Then, at “the matter, too” (211b29), he continues by considering matter.
First, he shows why matter seems to be place;
second, that it is not place, at “but the matter” (211b36; [465]).
He first says, therefore, that matter appears to be place if one should consider the changing of the bodies that succeed each other in the same place, as this occurs in some one subject that is at rest in a place, with attention being paid not to the fact that place is separate, but only to the fact that the change is occurring in one and the same continuum.