Since only universals are definable, substantial forms are universals.
If there were multiple substantial forms there would be no unity to being human multiple substantial forms implies multiple substances and multiple beings.
In my opinion, the indefinability of particulars makes it impossible for substantial forms to be particulars.
There are at least two senses in which substantial forms are eternal.
Accordingly, Scotus argues that the human being has at least two substantial forms.
The question, then, is whether the evidence against substantial forms being universals can be countered.
There are at least three serious questions about Aristotle's substantial forms.
But whether substantial forms are universals in Aristotle is a controversial matter.
Suárez counters that, on the contrary, substantial forms have significant explanatory work to do.
Consequently, some hypotheses, such as the "substantial forms" of scholastics, were ruled out.
But recall Thomas' rejection of the Plurality of Substantial Forms position.
