How able is form to take shape? For Aristotle, the form of a particular thing is not separate from the thing itself—any form is the form of something. He distinguishes form between “substantial” and “accidental”: “accidental” because they may undergo change, or be gained or lost, without thereby changing the first substance into something else or causing it to cease to exist. In contrast to “Substantial” that cannot be gained or lost without changing the nature of the substance of which they are predicated. Change, here, is analyzed as a material transformation: matter is what undergoes a change of form. Any change in the category of substance—a change of one kind of thing into another—is rather interesting. When a substance undergoes a change of quantity or quality, the same substance remains throughout. But does anything persist when one kind of thing turns into another?
This series of geometric constructs allude to the idea that a substance necessarily possesses at least one substantial form but may also possess a variety of accidental forms.