«إلا أن القضية الطبيعية لا تتصور ههنا»
The natural proposition is not conceived here.
In a categorical proposition, a natural proposition concerns a universal nature as such. A conditional proposition, however, primarily judges a relation between its component propositions, and its scope is treated in terms of suppositions.
The book therefore carries over singular, quantified, and indefinite forms, but not the natural form in the same way. The classifications are not identical across categorical and conditional propositions.