Unless the man who works in an office is able to "sell" himself and his ideas, unless he has the power to convince others of the soundness of his convictions, he can never achieve his goal. He may have the best ideas in the world, he may have plans which would revolutionize entire industries. But unless he can persuade others that his ideas are good, he will never get the chance to put them into effect. Stripped of non-essentials, all business activity is a sales battle. And everyone in business must be a salesman.