The idea of a "law of attraction" has been prominent in American culture at least since the early 1900s when it came to light as part of the New Thought movement. Napoleon Hill wrote about the law of attraction in at least two of his books and the wildly popular 2007 book "The Secret" by Rhonda Byrne deals with the same topic.
The basic idea behind the law of attraction is that "like attracts like" and so positive thoughts will attract positive outcomes while negative thoughts will bring about negative results. Losier's 2004 book "Law of Attraction" is credited by some readers as being a quick and clear explanation of this principle. It also includes scripts and other tools to help readers learn to apply the ideas involved in their daily lives.