Sometimes the boss is a man who cares for political power purely for its own sake, as he might care for any other hobby; more often he has in view some definitely selfish object such as political or financial advancement. He can rarely accomplish much unless he has another side to him.
 Theodore Roosevelt, Theodore Roosevelt; an Autobiography (1913). copy citation

Context

“And, in any event, if the men who are horrified by their wickedness were themselves as practical and as thoroughly in touch with human nature, the bosses would have a short shrift. The trouble is that the boss does understand human nature, and that he fills a place which the reformer cannot fill unless he likewise understands human nature. Sometimes the boss is a man who cares for political power purely for its own sake, as he might care for any other hobby; more often he has in view some definitely selfish object such as political or financial advancement. He can rarely accomplish much unless he has another side to him. A successful boss is very apt to be a man who, in addition to committing wickedness in his own interest, also does look after the interests of others, even if not from good motives. There are some communities so fortunate that there are very few men who have private interests to be served, and in these the power of the boss is at a minimum.” source