The principle of combining theory with practice applies the same to salesmanship as to the building of bridges, or anything else. The principle is fundamental. Therefore it is an essential part of organized thinking. A man does not become an able lawyer, or dentist, or doctor by merely acquiring a degree in these professions. He becomes able by applying the theory he learns in school, in the practical field of experience, and in no other way. There is no school that equals the good old University of Experience, and this is one school in which “cribbing” is not possible.
