Read Scott Alexander

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Links For October 2025

42 min • 6,423 words • 803 comments • 211 likes • podcast (38 min)

Scott Alexander presents 51 links covering AI progress and safety, political developments, scientific research, cultural oddities, and ongoing philosophical debates about miracles and education reform. Longer summary

Scott Alexander shares 51 links covering diverse topics including AI developments (agents, safety, consciousness research), political news (Ukraine policy, UK politics, Trump administration), science updates (climate predictions, genetics, bacteriophages), cultural curiosities (Shakespeare superfan plastic surgery, Soviet naming conventions, flag cones), health research (Alzheimer's prevention, shingles vaccine reducing dementia, kidney donation), and philosophical debates (Hume's argument against miracles, the Fatima miracle discussion). The post maintains Scott's characteristic blend of serious analysis and quirky observations, touching on everything from Bach's descendants in Oklahoma to the mystery of why AI still struggles with laundry folding despite mastering protein folding. Shorter summary

Recurring tags: book review (212), AI safety (69), links (62), genetics (58), climate change (33), Eliezer Yudkowsky (30), links roundup (28), OpenAI (27), AI progress (15), Anthropic (12), education reform (7), Richard Hanania (5), Freddie deBoer (5), kidney donation (3), David Hume (2), cultural history (2), NVIDIA (2), dementia prevention (2), political news (2), Kelsey Piper (2), Curtis Yarvin (2)

Jul 31, 2025

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Suddenly, Trait-Based Embryo Selection

56 min • 8,637 words • 748 comments • 407 likes • podcast (60 min)

Scott analyzes the sudden emergence of commercial trait-based embryo selection services, discussing both the scientific validity and ethical implications of selecting embryos for health outcomes, intelligence, and physical traits. Longer summary

Scott examines the recent development of commercial embryo selection services, particularly focusing on companies like Genomic Prediction, Orchid Health, Nucleus, and Herasight. He explains how the technology works, comparing different companies' claims and methodologies, and discusses both scientific challenges and ethical concerns. The post explores the potential benefits, like reduced disease risk and increased IQ, while acknowledging issues around cost, racial disparities, and social implications. A significant portion focuses on Herasight's critique of competitor Nucleus's scientific claims. The post concludes by placing this technology in the broader context of human enhancement and future technological developments. Shorter summary

Recurring tags: study critique (268), healthcare (56), IQ (32), bad science (30), genetic engineering (15), inequality (8), embryo selection (6), bioethics (5), AI implications (3)

Jun 26, 2025

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Missing Heritability: Much More Than You Wanted To Know

68 min • 10,491 words • 669 comments • 456 likes • podcast (62 min)

Scott explores the 'missing heritability' problem in genetics, where twin studies show traits like IQ and educational attainment are highly heritable but newer genomic methods find much lower heritability, analyzing various potential explanations for this discrepancy. Longer summary

The post examines the 'missing heritability' problem in genetics, where twin studies consistently show behavioral traits like IQ and educational attainment are substantially heritable (around 40-60%), while newer genomic methods find much lower heritability (around 15-20%). Scott reviews the history of behavioral genetics research, explains various study methodologies and their potential biases, and analyzes different hypotheses for this discrepancy. He examines whether twin studies might be flawed, whether newer methods might be missing important genetic effects, and whether educational attainment might be an unusually problematic trait to study. While acknowledging remaining mysteries, he tentatively concludes that twin studies are probably largely correct and that newer methods may be missing rare variants and genetic interactions. Shorter summary

Recurring tags: study critique (268), genetics (58), IQ (32), much more than you wanted to know (30), intelligence (22), twin studies (10), behavioral genetics (6), heritability (6), educational attainment (4), Eric Turkheimer (3)

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