From Galileo to today's amateur astronomers, scientists have been rebels, writes Freeman Dyson. Like artists and poets, they are free spirits who resist the restrictions their cultures impose on them. In their pursuit of nature's truths, they are guided as much by imagination as by reason, and their greatest theories have the uniqueness and beauty of great works of art.

Dyson argues that the best way to understand science is by understanding those who practice it. He tells stories of scientists at work, ranging from Isaac Newton's absorption in physics, alchemy, theology, and politics, to Ernest Rutherford's discovery of the structure of the atom, to Albert Einstein's stubborn hostility to the idea of black holes. His descriptions of brilliant physicists like Edward Teller and Richard Feynman are enlivened by his own reminiscences of them. He looks with a skeptical eye at fashionable scientific fads and fantasies, and speculates on the future of climate prediction, genetic engineering, the colonization of space, and the possibility that paranormal phenomena may exist yet not be scientifically verifiable.

Dyson also looks beyond particular scientific questions to reflect on broader philosophical issues, such as the limits of reductionism, the morality of strategic bombing and nuclear weapons, the preservation of the environment, and the relationship between science and religion. These essays, by a distinguished physicist who is also a prolific writer, offer informed insights into the history of science and fresh perspectives on contentious current debates about science, ethics, and faith.

Freeman Dyson has spent most of his life as a professor of physics at the Institute for Advanced Study in Princeton, taking time off to advise the US government and write books for the general public. He was born in England and worked as a civilian scientist for the Royal Air Force during World War II. He came to Cornell University as a graduate student in 1947 and worked with Hans Bethe and Richard Feynman, producing a user-friendly way to calculate the behavior of atoms and radiation. He also worked on nuclear reactors, solid-state physics, ferromagnetism, astrophysics, and biology, looking for problems where elegant mathematics could be usefully applied.

Dyson's books include Disturbing the Universe (1979), Weapons and Hope (1984), Infinite in All Directions (1988), Origins of Life (1986, second edition 1999), The Sun, the Genome and the Internet (1999), The Scientist as Rebel (2006, published by New York Review Books), and A Many-Colored Glass: Reflections on the Place of Life in the Universe (2010). New York Review Books will publish Dreams of Earth and Sky, a new collection of Dyson's essays, in April 2015. He is a fellow of the American Physical Society, a member of the National Academy of Sciences, and a fellow of the Royal Society of London. In 2000 he was awarded the Templeton Prize for Progress in Religion.