Read Concerning Being And Essence Online

PREFACE xxxiil 

dividuating conditions. But so far as the matter of knowledge 
is concerned intellect is absolutely dependent upon the senses. 
Natures exist as modes of accidents in corporeal substances, 
whereas essences exist as the modes of accident in the intellect; 
but as has been seen, essence is continuously conditioned by the 
nature so that the essence as abstracted is what the thing is in 
its proper and necessary mode apart from all contingent in- 
crements. The thing is that which is understood by means of 
the essence. 

Essences, being entia rationis or beings of reason, are that by 
virtue of which the intellect understands natures inasmuch as 
they are natures, namely, as such a necessary being freed from 
all improper accidents. Sensitive knowledge is the material 
cause of intellective knowledge and leads to the quiddity of the 
thing, that is, the formal equivalent of the thing according as 
it is that kind of thing and not another. 

The order of signification is the converse of the order of 
abstraction, but presupposes it. Abstraction is ordered thus: 
knowledge of singulars by sense precedes knowledge of the 
universal by intellect. First genera are abstracted and then 
species. Species are differentiated by a distinction of proper 
operation in the thing, just as animal is vital but man is 
rational. The genus is to the species as matter is to the form, 
since the species are differentiated from the genus by a proper 
distinction of act. 

Whereas the senses are not reflexive, not knowing their own 
acts, the intellect is reflexive and does know its own acts, powers 
and abstractions. The intellect knows that it is a substance 
through its accidents, and furthermore it knows what it is 
actually by the condition that the object of thought and the 
act of thought are one and the same. Hence it is that the 
intellect infers from its accidents to its substance. The concepts 
of logic are abstractions from entia rationis, beings of reason,