"Without knowledge of self there is no knowledge of God. Nearly all the wisdom we possess, that is to say, true and sound wisdom, consists of two parts: the knowledge of God and of ourselves."
John Calvin, Institutio Christianae Religionis
"Plato writes that the Form (or Idea) of the Good is the ultimate object of knowledge, although it is not knowledge itself, and from the Good, things that are just gain their usefulness and value."
The Form of the Good. A wiki excerpt.
(Source: Wikipedia)