In fact we may call it the noumenon or essential being of the class, as distinguished from the specific characteristics that differentiate the individual from others of the same class.
"The Law and the Word"
Thomas Troward
The outward fact is called the Phenomenon, and the corresponding inward principle is called the noumenon.
"The Law and the Word"
Thomas Troward
Still, the proposition does not assert that alone; it asserts that the Thing in itself, the noumenon Socrates, was existing, and doing or experiencing those various facts, during the same time.
"A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2)"
John Stuart Mill