Leo Tolstoy 
What Men Live By 

It once occurred to a certain king, that if he always knew the right time to begin everything; if he knew who were the right people to listen to, and whom to avoid; and, above all, if he always knew what was the most important thing to do, he would never fail in anything he might undertake.
And this thought having occurred to him, he had it proclaimed throughout his kingdom that he would give a great reward to any one who would teach him what was the right time for every action, and who were the most necessary people, and how he might know what was the most important thing to do.
And learned men came to the King, but they all answered his questions differently…