Ignorance is in relationship to content; it is not just a spirit of ignorance. In verse 21 it speaks of "the truth in Jesus." Truth is content, truth has something to do with reason. Truth has something to do with the rational creature that God has made us. The dilemma here in the internal world is not just some sort of grey fog, it is in relationship to content.

The Complete Works of Francis A. Schaeffer: A Christian view of spirituality (ed. 1982)