LIGHT

The usual popular-science history of light begins with the ancient Greeks and peters out soon after Einstein, but this fine account by Smithsonian contributing writer Watson (Freedom Summer: The Savage Season of 1964 that Made Mississippi Burn and Made America a Democracy, 2010, etc.) paints with a broader brush.

The author emphasizes that humans paid attention to light and darkness long before they tried to understand it. With increasing knowledge came conveniences and inventions along with new ways of observing the world—i.e., art. Throughout the book, Watson gives close attention to both science and art. All religions venerate light, which the author illustrates in his first 60 pages, including many quotes from sacred texts and holy men that show great passion without actually explaining anything. Ancient thinkers argued a problem that now seems odd. Do we see because light flows from our eyes toward the world or in the opposite direction? Aristotle got it wrong; only in the Middle Ages did Arab scientists deliver a convincing argument. Watson’s artistic Renaissance begins with a new birth of vision. Perspective in painting appeared in the 15th century, as artists teased out the secrets of light, shading, and color. The scientific Renaissance arrives in the following chapter, and Isaac Newton receives his own (gravity gets the headlines, but his optical studies were equally revolutionary). The author proceeds with chapters devoted to physics, the humanities, or both (19th-century France invented both photography and impressionism). Watson’s examination of technology monopolizes the book’s final third, as the century and a half that began with Thomas Edison’s incandescent bulb (already fading into obsolescence) has swamped the world in light pouring out of lasers, masers, LEDs, and optical scanners.

An ingenious combination of science and art history.