Again and again, lest at any time while you study you might fall below 100% in _absolute assurance_, you will read in these chapters the assertion that your success can be made _certain_. This statement is not an exaggeration. It is necessary that you accept it literally throughout your reading of this set of books. Do not take it "with a grain of salt." The taste of the declaration that the selling process makes success sure will become familiar after these many repetitions. Realize when you come upon the repeated idea as you proceed with your study that your continued reading should frequently be reenforced by a steadily growing conviction that you _are_ mastering the sure way to succeed. You believe in yourself more than you did when you began to read this book. This increasing faith should develop to complete confidence when you have dug _into_ the text of both "Certain Success" and "The Selling Process," and have dug _out_ every idea in the twenty-four chapters.
[Sidenote: Salesmanship Not a Science But an Art]
At the outset of your present study comprehend that salesmanship is not a _science_. Rather, it is an _art_. Like every other art, however, it has a _related_ science. Selling is a _process. Knowledge about the principles and methods_ that make the process most effective is the related _science_. But such knowledge supplies only the best foundation for building success by the _actual practice_ of most effective salesmanship. The master salesman practices the scientific principles and methods he has learned until the _skillful use_ of his knowledge in every-day selling becomes _second nature_ to him. Thus, and thus only, is his _art_ perfected.
You will gain _knowledge_ from these books about _how_ to sell with assurance the true idea of your best capabilities--about _how_ to sell any "goods of sale" unfailingly. But you can develop the _skill_ necessary to the _actual achievement_ of certain success only if you _continually use_ what you learn about the selling process. You must perfect your selling _art_ by the intelligent employment of every _word_ and _tone_ and _act_ of your life to attract other men to you, and to impress on them convincingly true ideas of your particular ability.