Read Concerning Being And Essence Online

CHAPTER Six 

IT NOW remains to see how essence exists in accidents, for 
how it exists in all substances has been discussed. And be- 
cause, as has been said, essence is what is signified by means of 
definition it is necessary that they (accidents) possess essence 
in the mode in which they have definition. But they have an 
incomplete definition because they cannot be defined unless a 
subject is posited in their definition; and this is because they 
do not have existence by virtue of themselves (per se) freed 
from (absolutum) the subject. But just as a substantial exist- 
ence ensues from form and matter when composited, so, too, 
an accidental existence ensues from accident and subject when 
the accident advenes to the subject. And therefore neither has 
the substantial form itself complete essence, nor has matter; 
because likewise in the definition of substantial form it is neces- 
sary to posit that of which it is the form, and so its definition 
is by virtue of the addition of something which is outside its 
genus, as is also the definition of the accidental form. Whence 
in the definition of soul body is posited by the naturalist who 
considers the soul only inasmuch as it is the form of a physical 
body. But nevertheless there is a difference between substantial 
form and accidental form because, just as substantial form does 
not have an absolute existence by virtue of itself without that 
to which it advenes, so neither does that to which it advenes, 
namely, matter. And therefore from the conjunction of both 
ensues that existence in which the thing subsists by virtue of 
itself (per se), and from them is effected a unity by virtue of 
itself (unum per se: a substantial unity) for the reason that 

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