The heart exploits the mind to justify what the heart wants

"One profound biblical insight we need to embrace is that our heart exploits our mind to justify what the heart wants. That is, our deepest desires precede the rational functioning of our minds and incline the mind to perceive and think in a way that will make the desires look right. It is an illusion to think that our hearts are neutral and incline in accordance with cool, rational observation of truth. On the contrary, we feel powerful desires or fears in our hearts, and then our minds bend reality to justify the desires and fears." - John Piper, Taste and See: Savoring the Supremacy of God in All of Life (Sisters, Or. : Multnomah Publishers, 2005), page 28