That’s what Obama’s really saying here.
“What matters at the Supreme Court is those 5% of cases that are truly difficult. In those cases, adherence to precedent and rules of construction will only get you through 25 miles of the marathon. That last mile can only be determined on the basis of one’s deepest values, one’s core concerns, one’s broader perspectives on how the world works and the depth and breadth of one’s empathy.
“In those difficult cases, the critical ingredient is supplied by what is in the judge’s heart.”