Martin Luther King's policy of non-violent protest in the struggle for civil rights in the United States during the second half of the twentieth century led to fundamental shifts in American government policy relating to segregation, and a cultural shift in the treatment of African Americans.

One of the most widely read books in the social sciences, Purity and Danger established Mary Douglas as one of the twentieth century's leading social scientists. She delves in great detail into existing arguments that portray traditional societies as "evolving" from "savage" beliefs and explains why she believes those arguments are wrong.

Wollstonecraft's 1792 work sets out all the chief principles of feminist thought developed by later feminist writers and activists. Wollstonecraft asserts that the differences between the sexes are the result of nurture, not nature, and outlines a theory for the equal education of girls and boys.

Classical economics suggests that market economies are self-correcting in times of recession or depression, and tend toward full employment and output. But English economist John Maynard Keynes disagrees. In his ground-breaking 1936 study The General Theory, Keynes argues that traditional economics has misunderstood the causes of unemployment.

First published in 1980, Competitive Strategy contradicted the accepted wisdom of the time that said firms should focus on expanding their market share. Instead, Porter claimed, they should analyze the five forces that mold the environment in which they compete: new entrants, substitute products, buyers, suppliers, and industry rivals.

In their 1990 work, Gottfredson and Hirschi introduce a new and comprehensive theory of crime. At the time, crime researchers tended to focus on environmental factors that led to crime, not on the criminals themselves, and were inclined to think about crime only from their particular academic perspective. Ideas about what caused crime, and how to prevent it, were often in conflict.

A crititcal analysis of the first work written for the general public by the highly influential American economist Milton Friedman. Capitalism and Freedom argues that economies and societies work best when a free market functions with minimal government interference.

Though written more than 500 years ago, Niccolo Machiavelli's The Prince is still both widely read and very influential. Readers turn to it for its direct advice on the question of how to attain - and retain - power.

Philip Zimbardo is fascinated by why people can behave in awful ways.

Carson's 1962 work Silent Spring was one of the first books ever to highlight environmentalist issues.