Peter Drucker, in his autobiography, Adventures of a Bystander, writes of Marshall McLuhan and Buckminster Fuller:

Bucky Fuller and Marshall McLuhan exemplify for me the importance of being single-minded. The single-minded ones, the monomaniacs, are the only true achievers. The rest, the ones like me, may have more fun, but they fritter themselves away. The Fullers and the McLuhans carry out a "mission"'; the rest of us have "interests." Whenever anything is being accomplished, it is being done, I have learned, by a monomaniac with a mission.

What, if anything, do you wish to accomplish? Can you make it your mission? Can you be monomaniacal about it?