The great historian of science I. B. Cohen explores how numbers have come to assume a leading role in science, in the operations and structure of government, in marketing, and in many other aspects of daily life. Consulting and collecting numbers has been a feature of human affairs since antiquity--taxes, head counts for military service--but not until the Scientific Revolution in the twelfth century did social numbers such as births, deaths, and marriages begin to be analyzed. Cohen shines a new light on familiar figures such as Thomas Jefferson, Benjamin Franklin, and Charles Dickens; and he reveals Florence Nightingale to be a passionate statistician. Cohen has left us with an engaging and accessible history of numbers, an appreciation of the essential nature of statistics.