Simple eternity is God’s eternity, the non-temporal mode of being enjoyed by God.  Like Augustine before him in Confessions 12.40, Grosseteste thinks we can speak of eternity as before time and of time as after eternity, provided we bear in mind that the terms “before” and “after” are in this connection employed in non-temporal senses.  According to Grosseteste, if Aristotle had more fully grasped simple eternity he would have realized his arguments for the eternity of the world rest on a failure to recognize non-temporal notions of before and after. Aristotle, he thinks, assumes in two of his arguments for the eternity of the world that a first movement would have to have been preceded by a potentiality for this movement and thus by time. But since, according to Aristotle, time requires movement and a potentiality for something can only be exercised through a movement, there follows the absurdity that the first movement would not be the first movement. Thus time and movement must be without a beginning. Grosseteste objects that although the first movement exists after not existing and that there was indeed a potential for that movement before it, in this context “was” and “before” refer to the relation of eternity to time and are used in a non-temporal sense. The first movement was preceded by a potentiality for itself, not in time, but in God’s eternity, and the actualization of this potentiality involves no movement or change in God. As for Aristotle’s third argument that there cannot be a first instant, hence nor a beginning of time or change, because an instant is a link between past and future, Grosseteste responds that this conception of an instant will appeal only to someone already committed to the eternity of time and change.