The great quest of the Enlightenment thinkers of the 17th and 18th centuries was the development of a scientific way of thinking that could unify all human knowledge. Emerging principles of the scientific method—curiosity, independent thinking, theories, publicly reproducible tests of theories, constant revision—might prove useful not only in the natural sciences but also in the humanities, including philosophy, the nascent social sciences, and the arts.

This quest produced a tremendous growth in scientific knowledge and, with it, the burgeoning of technology. These achievements helped boost economic growth along with advances in human lifespan and happiness. The humanities, however, rejected Enlightenment ideas during the 19th century in favor of a Romantic movement that emphasized human passions and the pursuit of creative individualism and the glories of ecstasy. Indeed, art, music, and literature flourished during this period.

During the 20th century, the social sciences began to take definite shape and make progress in the study of human cultures, psychology, and the nature of the mind and brain. Much of this progress stemmed from the adoption of scientific research techniques that greatly increased knowledge about, and better understanding of, human social interactions and the creative process.