Every being which is endowed with reason, and transgresses its statutes and limitations, is undoubtedly involved in sin by swerving from rectitude and justice.
On First Principles, Bk. 1, ch. 5; vol. 1, p. 45.
As the eye naturally seeks the light and vision, and our body naturally desires food and drink, so our mind is possessed with a becoming and natural desire to become acquainted with the truth of God and the causes of things.Origen