Medical doctors are trained to focus on the care of the body.  Clerics, on the care of the soul.  Philosophers, on the care of the mind.  Which is most important is disputable, as all things are.  But it is the vocation of the philosopher, as thinker, to consider all parts of what it is to be human, since the judgments arrived at in the other two domains depend upon the ideas that are accepted, rejected, or left in abeyance.  Ideas are the domain in which the philosopher lives and gives.