That to which causation is attributed are matter and form themselves...

That to which causation is attributed are matter and form themselves, and that to which being an effect is attributed is the conjunction of them, under the condition that they are joined and have a compound structure, that is, if matter and form are viewed apart from being conjoined and being compounded, each of them may be considered a cause of the ‘whole.’ Whenever they are considered under the condition of being joined, compounded and in the form of a whole, we call it the effect of its parts, for the existence of the whole depends on the existence of its parts.

This answer returns us to the point that the difference between cause and effect is relative to our perspective and respect ( i‘tibār ), while the causal relation is a matter of fact and is independent of respects (although in another sense in regard to whatish concepts, it is called respectival ( i‘tibārī )).

The truth is that the application of [the concept of] cause to matter and form, and the application of [the concept of] effect to the conjunction of them is not free from imprecision, as was previously indicated. And if a body which is apt to take a new form is allowably called the material cause for the succeeding existent, this is because it prepares the grounds for the latter’s appearance. Another point may be made with regard to the fundamentality of existence.

Since the causal relation really holds between two existences, it is clear that the whatness of something cannot be considered the cause of its existence, for whatness in itself has no reality such that it could really be the cause of something. Likewise, a whatness cannot be considered the cause of another whatness. It is possible that it will be said that philosophers have divided causes into two types: causes of whatnesses and causes of existence.

An example of the first type is the causation of line and surface for the whatness of a triangle, and the causation of matter and form for the whatness of body. An example of the second type is the causation of the existence of fire for the existence of heat. Thus it is known that in their view there exists a kind of causal relation among whatnesses.