A vegetarian and meat-eater collaborate to analyze the impacts of eating meat, concluding that reduced consumption is beneficial but not as clear-cut as some might think. Longer summary

This post is an entry to the 2019 Adversarial Collaboration Contest, where a vegetarian and a meat-eater investigate the ethical, health, and environmental impacts of eating meat. They explore animal consciousness, factory farming conditions, human happiness set points, health outcomes, environmental effects, and costs of switching diets. They conclude that reducing meat consumption, especially chicken, is beneficial overall, but the case is not as strong as some vegetarians might assume. Shorter summary

TracingWoodgrains and Michael Pershan analyze the effectiveness of ability grouping, acceleration, and personalization software in serving advanced students in the education system. Longer summary

This post is an entry to the Adversarial Collaboration Contest by TracingWoodgrains and Michael Pershan, discussing whether the education system adequately serves advanced students. It examines three main approaches: ability grouping, acceleration, and personalization software. The authors review research on each approach, discuss their pros and cons, and explore the tensions between different educational goals. They conclude with practical advice for parents, educators, and educational reformers. Shorter summary

Scott shares diverse links ranging from optical illusions and Bitcoin drama to educational research and medical controversies, with commentary on methodology and social implications. Longer summary

A collection of interesting links covering various topics. The post starts with scientific curiosities like the McCullough Effect optical illusion and updates on potential alien megastructures, then moves through educational research, Bitcoin controversies, and employment discrimination. It includes discussions of medical issues in the UK, interesting methodologies in gender research, and immigration policies. The post ends with various studies on economics, psychology, and social issues, including an intriguing study about Vietnam veterans' children's income. Shorter summary

Scott Alexander defends psychiatry's use of 'chemical imbalance' theory, arguing it was meant to emphasize depression's biological basis rather than claiming a simple serotonin deficiency. Longer summary

Scott Alexander responds to criticisms of psychiatry's use of the 'chemical imbalance' theory of depression. He argues that psychiatrists never claimed depression was simply a serotonin deficiency, but rather a complex interaction of brain chemicals. He explains that the term 'chemical imbalance' was used to emphasize depression's biological basis and help people take it seriously, rather than viewing it as a personal failure. Scott provides evidence that serotonin and other neurotransmitters are indeed involved in depression, while acknowledging the full picture is more complicated. He concludes that framing depression in terms of brain chemistry remains useful, even if 'chemical imbalance' is no longer the best terminology. Shorter summary

The author revisits their belief in genetic determinism, presenting evidence that environmental factors, especially in divorce, have significant non-genetic effects on children's outcomes. Longer summary

The post discusses the author's initial belief in the genetic determinism thesis from 'The Nurture Assumption', which argues that parenting has little effect on children's outcomes compared to genetics. The author then presents evidence from divorce studies that challenge this view, showing that environmental factors, particularly family conflict, do have significant effects on children. The post reviews several studies that disentangle genetic and environmental effects of divorce, concluding that there are indeed non-genetic negative impacts of divorce on children. The author acknowledges being wrong about shared environment effects being negligible and suggests that short-term environmental impacts can have long-lasting consequences. Shorter summary

Scott Alexander proposes a 'Thrive/Survive Theory' explaining political ideologies as optimizations for different environments, with rightism for survival and leftism for thriving in safety. Longer summary

Scott Alexander proposes a 'Thrive/Survive Theory' to explain the political spectrum. He suggests that rightism is optimized for surviving unsafe environments, while leftism is optimized for thriving in safe environments. The post explores how this theory explains various aspects of political ideologies, including their stability across cultures, correlation with other preferences, and the gradual leftward drift of society over time. Scott uses thought experiments involving zombie apocalypses and utopian futures to illustrate how different environments might shape political views. He also discusses how this theory relates to developmental psychology and historical trends. Shorter summary