Theoria is also known as illumination. It is the second degree of the spiritual life and includes the contemplation of God. In other words, theoria makes thinking of God as much of a habit as breathing.
In theoria, we rediscover the true transparency of the mind. We begin to recognize divine Wisdom operating in and around us, and glorify Him because of it. We also become more conscious of the greatness of God Himself.
At another, deeper level, theoria promotes a deepening encounter with the Lord through the 'uncreated light'. Freed from cosmic laws and enslavement to to the world, we begin to converse with God. Consequently, we can neither live nor organize anything without praying. Thus, theoria transforms us more and more into that, which we contemplate: God.
Ongoing desire for and participation in theoria leads us into theosis, which is the third degree of the spiritual life.