In the United States today tests of the ability to perform well in school divide society and define opportunity. Higher education has become a major focus of aspirations people hold for their children, and educational testing determines who qualifies for higher education. This history recounts the development of intelligence testing and its early purpose as a way to unseat the quasi-hereditary white male elite that had run the United States until the end of World War II. U.S. citizens have come to believe that the system of standardized tests is the only possible embodiment of the principle of a U.S. meritocracy. How this came about, what it really means for equal education, and the alternatives that may be developed are explored. "Book One: The Moral Equivalent of Religion" contains 10 chapters on the history of ability testing. "Book Two: The Master Plan" describes the development of the current system, and "Book Three: The Guardians" discusses the system as it operates today. (Contains 350 endnotes and an index.) (SLD)