Everything of depth requires the heart foremost.  Everything of substance and structure requires the mind.  I think the closest analogy is the body and the spirit.  They are inseparable, but I believe the body is in the service of the spirit, like a vehicle is in the service of the occupant.  
I recently was in a difficult mediation (are there any easy ones?).  As a lawyer, I work hard to find the “soul” of a case–the heart.  Yet, all that effort really misses the mark if I don’t go to the “heart” of my client.  It is there I’ll find if the case has the dramatic clarity and truth that is needed to carry it forward.
  The mediator, somewhere in the middle of a long day of work, asked my client a transformative question that opened a door to another universe:  “How did that affect your heart?”  My client’s face softened, tears formed at her eyes, and her voice quivered as she relived the pain.  I connected with the emotion immediately. 

 Suddenly I saw what the case was about.  It was the reality of this woman’s pain.  My job was to tell that story, not the one that captured only the “theme” of the case.  That story, if it had any “fire” at all, is a story of emotions.  The evidence, the documents, the rules of civil procedure, the rules of evidence, the order of proof, the rulings on objections, the statements of law, and the jury instructions– all of that, I came to see in an instant, is window dressing, important yes, but just window dressing.