Courage - the word itself comes from the old french word for heart; coer.(now coeur). So courage is literally belonging to the heart.
"I know that courage comes from the heart because the head would say 'no'."
Courage is not fearlessness. Quite the contrary. Courage feels the fear and acts anyway; it is strong enough to overcome our most basic neurological response to avoid danger or threat. Courage knows that failure will extract a very high price and yet still takes that risk. Sometimes it is a simple gamble based on the odds of failure versus the value of a higher prize; but that's a little "head" interference.