Hotsprings Today

Over the last several decades, semiconductors have enabled a sprawling ecosystem of modern technologies—microchips in nearly every machine, LEDs for efficient lighting, solar photovoltaics, fiber-optic communications, and digital imaging sensors. But long before the transistor, a similarly expansive technological world grew around the vacuum tube: an evacuated (often glass) tube in which electrons flow between electrodes. Vacuum tubes emerged from two parallel lineages. One came from gas discharge experiments made possible by early vacuum pumps, where rarefied gases glowed under electrical current. Work by Faraday, Plücker, Crookes, and others led to the study of “cathode rays,” culminating in Roentgen’s discovery of X-rays and J.J. Thomson’s identification of the electron. The second lineage came from incandescent lighting: Edison’s investigations into bulb darkening revealed the “Edison Effect” (thermionic emission), which John Fleming used to create a rectifying “valve,” and Lee de Forest extended into the triode amplifier—vital to telephony, radio, television, and early computing. Beyond logic and amplification, tube-based devices powered oscilloscopes and TVs (cathode ray tubes), enabled new lighting (neon and fluorescent), and generated radiation from X-rays to microwaves (magnetrons, klystrons, gyrotrons), many still used today. The broader lesson: breakthrough technologies don’t just climb one S-curve—they can trigger a “Cambrian explosion” of specialized devices with long-lasting impact.

In a wide-ranging Hoover History Lab conversation, historian Stephen Kotkin argues that good history starts with strong questions—and the discipline to hunt for disconfirming evidence, not just proof that flatters your thesis. The archive is essential, but also dangerous: state records reflect the state’s obsessions and blind spots, so historians have to triangulate across genres—periodicals, memoirs, travel accounts, local knowledge—to see what official paperwork misses. He also describes the historian’s craft as a practice of empathy: not sentimental identification, but the hard work of understanding motives and mental worlds, including those of perpetrators, without excusing them. Kotkin rejects “history is one damn thing after another” by insisting historians must pair depth with pattern recognition across cases. The payoff is not just better scholarship, but better public reasoning—especially against “junk history,” where lazy analogies (his example: reflexive Munich comparisons) substitute for analysis and shut down debate. He champions “analytical narrative”—showing rather than sermonizing—and writing that respects both specialists and the public by keeping the audience in view. Turning to today’s information ecosystem, he treats AI “slop” as a demand problem as much as a supply problem, and warns that attempts to suppress speech often produce perverse, unintended consequences—history’s recurring lesson.