If the (Stoics) say that the "reasons" are only modified matter, they
then admit that qualities are modes, and the (Stoics) should locate
the reasons in the fourth category, of relation. If however relation
be something different from modality, in what does that difference
consist? Is it that modality here possesses greater reality? But if
modality, taken in itself, be not a reality, why then make of it a
category? Surely it would be impossible to gather in a single category
both essence and non-essence. In what then does this modification of
matter consist? It must be either essence or non-essence. If it be
essence, it is necessarily incorporeal. If it be non-essence, it is
nothing but a word, and matter alone exists. In this case, quality
is nothing real, and modality still less. As to the fourth category,
relation, absolutely no reality whatever will inhere in it. This Stoic
system, therefore, contains nothing else but matter.