For many people, numbers hold a significance that goes beyond their numerical value. They possess an inner nature and a magical character. Numerologists and number mystics attribute extraordinary power to numbers over events. A pyramidologist, for example, measures his pyramid and concludes from the numbers that the world will end on August 20, 1953. Stock prices fluctuate up and down because the Fibonacci numbers influence them. The Bible is full of sevens and thirteens because God intended it that way, and biorhythm theorists claim that humans oscillate in cycles of 23, 28, and 33 days, thus our behavior is determined by these figures. There is hardly an area that is not supposedly influenced by some numbers. Underwood Dudley has closely examined their secret meanings and guides the reader in his entertaining book.