Dean Keith Simonton examines uncommon people; those creators and leaders whose impact on their own and later times has been so great that they deserve the label "genius". A simultaneous look at creativity and leadership is itself uncommon, and the comparison shows that when creators and leaders act at genius levels they have many similarities. What it is that causes them to stand out above others? Is it family background, education, intelligence, the nature of the times in which they live? Is there a peak age for creativity? Simonton believes that if we subject the lives of the eminent to scientific analysis we may be able to discover general laws of history and social behavior. To do this he defines a discipline called historiometry. He begins with an explanation of the method: choosing a unit of analysis, be it individual philosophers, historic land battles, or classical melodies; defining and calculating the crucial variables; and teasing out with advanced statistical analysis the most probable causal connections in the data.