A wise, personal, and wide-ranging meditation on science and society by the Nobel Prize–winning author of To Explain the World. For more than four decades, one of the most captivating and celebrated science communicators of our time has challenged the public to think carefully about the foundations of nature and the inseparable entanglement of science and society. In Third Thoughts Steven Weinberg casts a wide net: from the cosmological to the personal, from astronomy, quantum mechanics, and the history of science to the limitations of current knowledge, the art of discovery, and the rewards of getting things wrong. Winner of the Nobel Prize in Physics and author of the classic The First Three Minutes, Weinberg shares his views on some of the most fundamental and fascinating aspects of physics and the universe. But he does not seclude science behind disciplinary walls, or shy away from politics, taking on what he sees as the folly of manned spaceflight, the harms of inequality, and the importance of public goods. His point of view is rationalist, realist, reductionist, and devoutly secularist. Weinberg is that great rarity, a prize-winning physicist who is entertaining and accessible. The essays in Third Thoughts, some of which appear here for the first time, will engage, provoke, and inform―and never lose sight of the human dimension of scientific discovery and its consequences for our endless drive to probe the workings of the cosmos.