for it, then it must likewise be of the very nature of the other that separation is impossible for it. Their likeness would therefore preclude parts in contact from moving apart and parts that are apart from coming into contact. For if one separates from what it touches, this establishes that it admits of separation, which prevents it from being like something that does not admit of separation.

Moreover, when two things are alike in essence and attributes but differ in size, neither need equal the other in matters determined by size—as with a small dinar compared with a large dinar.

What further clarifies this is that such separation changes a thing’s essence, just as it changes and alters its attributes. For when fire and air lose their respective properties of being fire and air, they cease to be fire and air, or the fiery parts cease to be fire and air. Likewise, whenever something whose essence depends upon its being united is dispersed and torn apart, it ceases to retain its essence. This applies to all composite things, such as the human body when it is cut into very small pieces. Indeed, the essence of many bodies changes through division just as it changes through transformation, even if the body itself is simple.

In sum, the basis of this argument is that he posited a likeness and maintained that whatever is possible for one must therefore be possible for the other. One may reply: The likeness we have conceded does not include anything entailing the possibility of division or the possibility of each part occupying the place of another. Nor does this fall within the meaning of