In this lecture, Lawrence H. White — Professor of Economics at George Mason University and Senior Fellow at the F. A. Hayek Program for Advanced Study in Philosophy, Politics, and Economics at the Mercatus Center — offers a comprehensive reading of one of the most consequential books of the 20th century.

Published in 1944, Hayek's The Road to Serfdom marked a turning point in his career: from technical monetary economist to public intellectual. White traces the historical context that made the book necessary — the intellectual prestige of central planning in the 1930s, FDR's New Deal and its corporatist inspiration, and the chilling admiration some American progressives harbored for Mussolini's "efficient" state apparatus.

White walks through the book's core arguments: why central planning is not merely economically inefficient but inherently incompatible with the rule of law and individual liberty; why partial interventionism tends to escalate rather than stabilize (Mises's logic of interventionism); and why, in a centrally planned system, it is the least scrupulous who tend to rise to positions of power.

The lecture also examines how the book was received — from Churchill's rhetorical overreach in the 1945 British elections to Paul Samuelson's influential (and deeply flawed) misreading — and closes with Keynes's famous letter from the ship to Bretton Woods: enthusiastic agreement in principle, followed by the conviction that good planning by the right people would make Hayek's warnings moot.

In this remarkable conversation, physicist and author Brian Greene sits down with Edward Witten — widely regarded as the greatest theoretical physicist of our era and the only scientist ever to receive the Fields Medal, the highest honor in mathematics — picking up a dialogue that began 39 years earlier at Harvard in 1986.

The evening explores some of the deepest questions in fundamental physics: what is quantum mechanics, and why is it so difficult to reconcile with Einstein's general relativity? Why does gravity continue to resist quantization? And where do we stand today in the search for a unified theory of everything?

At the heart of the discussion is String Theory — its history, its genuine breakthroughs (including the revolution of the 1990s and Maldacena's celebrated duality between gauge theory and gravity), and its still-unanswered challenges. Witten is candid: physicists have uncovered a vast and mathematically breathtaking structure, but the unifying principles behind it remain unknown. Unlike Einstein, who developed the concepts of general relativity first and then found the mathematics to match, string theory was stumbled upon without anyone knowing what it really was — and in many ways, that mystery persists to this day.

Greene and Witten also reflect on the sociology of science: the early resistance to string theory within the physics community, the courage required to bet an entire career on a radical idea, and the long periods of waiting and uncertainty that define life as a theoretical physicist. Witten admits that much of the time, doing research simply feels like hanging around doing nothing.

Physics has achieved extraordinary things — it can explain the behavior of matter from subatomic particles to galaxy clusters, trace the history of the universe back to fractions of a second after the Big Bang, and predict experimental outcomes with stunning precision. And yet, says theoretical physicist Sean Carroll, the deepest questions remain stubbornly, fascinatingly open.

In this lecture delivered at the Darwin College Lecture Series at Cambridge, Carroll takes listeners on a tour of the frontiers of modern physics — not the textbook version, but the genuinely unsettled, contested, and mysterious one. Three big themes structure the talk: the nature of quantum mechanics, the nature of space, and the nature of time.

Along the way, Carroll unpacks why physicists still don't agree on what quantum mechanics actually means — not just how to use it. He explores the many-worlds interpretation, the puzzle of quantum entanglement, and why the measurement problem is far from solved. He then turns to space and time: why does time have a direction at all? What does entropy really tell us about the arrow of time, the origin of complexity, and the fact that we — conscious beings — exist right now, at what Carroll calls "the fun Friday night of cosmic history"?