Why Worry?

Here are the few paragraphs from the book,
No apology is needed for adding another to the treatises on a subject whose importance is evidenced by the number already offered the public.

The habit of worry is not to be overcome by unaided resolution. It is hoped that the victim of this unfortunate tendency may find, among the homely illustrations and commonplace suggestions here offered, something to turn his mind into more healthy channels. It is not the aim of the writer to transform the busy man into a philosopher of the indolent and contemplative type, but rather to enable him to do his work more effectively by eliminating undue solicitude. This elimination is consistent even with the "strenuous life."
One writer has distinguished between normal and abnormal worry, and directed his efforts against the latter. Webster’s definition of worry (A state of undue solicitude) obviates the necessity of deciding what degree and kind of worry is abnormal, and directs attention rather to deciding what degree of solicitude may be fairly adjudged undue.