"But why doesn't the heart want God, trust God, look childlike to God for life's joys and securities? Why doesn't the heart seek final good where it can actually be found? Why turn again and again, in small matters and large, to satisfactions that are mutable, damaging, and imperiled?....Because the heart wants what it wants. That's as far as we get. That's the conversation stopper. The imperial self overrules all. Inquiring into the causes of sin takes us back, again and again, to the intractable human will and to the heart's desire that stiffens the will against all competing considerations. Like a neurotic and therapeutically shelf-worn little god, the human heart keeps ending discussions by insisting that it wants what it wants....The trouble is that this is only a redescriptioin of human sin, not an explanation of it----let alone a defense of it. Our core problem, says St. Augustine, is that the human heart, ignoring God, turns in on itself, tries to lift itself, wants to please itself, and ends up debasing itself. The person who reaches toward God and wants to please God gets, so to speak, stretched by this move, and ennobled by the transcendence of its object. But the person who curves in on himself, who wants God's gifts without God, who wants to satisfy the deires of a divided heart, ends up sagging and contracting into a little wad. His desires are provincial. 'There is something in humilty which, strangely enough, exalts the heart, and something in pride which debases it.' (Augustine, City of God)"

-----Cornelius Plantiga Jr., "Not the Way It's Supposed to Be: A Breviary of Sin"