A replication of a 2023 neuroscience study on brain entrainment and learning found that the original effect likely doesn't exist, revealing how the study obscured key issues through statistical averaging and highlighting how AI tools are democratizing scientific scrutiny. Longer summary

Sasha Putilin received an ACX grant to replicate a 2023 study claiming that flickering lights synchronized to individual brain rhythms could boost learning speed threefold. The $32,000 replication with 12 participants (versus 80 in the original) found no such effect. Upon examining the original data more closely, Putilin discovered the apparent effect was driven entirely by a few participants with large negative learning rates (getting worse over time) who happened to all be in one experimental group. The original study had obscured this pattern by presenting averaged data rather than individual results. Putilin argues this exemplifies 'cargo-cult statistics' where researchers mechanically apply statistical rituals without critically examining underlying data. The post concludes by suggesting AI tools are democratizing meta-science, enabling anyone to audit published research that previously required expert-level effort. Shorter summary

A review of Joe Henrich's 'The Weirdest People in the World', examining its argument that the Western Church's marriage regulations led to WEIRD psychology and modern economic growth. Longer summary

This book review examines Joe Henrich's 'The Weirdest People in the World', which argues that the Western Church's Marriage and Family Program (MFP) dismantled intensive kinship networks, leading to WEIRD (Western, Educated, Industrialized, Rich, and Democratic) psychology and modern economic growth. The reviewer discusses the book's scientific approach to European history, its extensive coverage of various topics, and raises questions about the intentionality of historical actors and the future implications of WEIRD psychology. Shorter summary

Scott Alexander presents a monthly collection of 42 diverse links covering topics from science, politics, culture, and technology, highlighting interesting findings and current events. Longer summary

This post is a collection of 42 diverse links and topics, ranging from scientific studies to political news and cultural observations. Scott Alexander curates these links monthly, covering a wide array of subjects including zoology, sociology, economics, psychology, technology, and more. The links often highlight interesting or surprising findings, such as studies on cult demographics, obesity research controversies, and the effects of testosterone on belief in minority positions. Scott also includes humorous content, political commentary, and discussions on current events and social trends. Shorter summary

Scott Alexander examines the hypothesis that sexual purity taboos evolved to prevent STI spread, considering historical STI prevalence and cross-cultural taboos. Longer summary

Scott Alexander explores the hypothesis that cultural evolution created sexual purity taboos to prevent the spread of sexually transmitted infections (STIs). He discusses the historical prevalence of STIs, particularly syphilis, and examines common sexual purity taboos across cultures. The post considers both STIs and false paternity as potential drivers of these taboos, weighing evidence for each. Scott also investigates taboos on homosexuality, discussing their variation across cultures and potential links to STI transmission. While he concludes that STIs likely played a role in the evolution of these taboos, he acknowledges that the evidence is circumstantial and more research is needed. Shorter summary

Scott proposes that value differences arise from people crystallizing heuristics at different levels, rather than from fundamental, incomprehensible differences in values. Longer summary

Scott explores the idea that value differences stem from people operating at different levels of a conceptual ladder, from explicit models to emotional experiences to reified essences to endorsed values. He argues that this perspective can help people understand each other better, as differences often arise from where individuals choose to crystallize heuristics rather than from fundamental, incomprehensible value differences. The post discusses various examples of this process, from nutrition to punishment to environmental preservation, and examines factors that influence where people place themselves on this ladder, such as intelligence, education, and personal experience. Shorter summary