Scott Alexander examines recent studies on the Fraternal Birth Order Effect, finding evidence for a broader sibling birth order effect on homosexuality, though its exact nature and mechanism remain debated. Longer summary

Scott Alexander reviews recent studies on the Fraternal Birth Order Effect (FBOE), which suggests that men with more older brothers are more likely to be gay. He discusses three key studies: Frisch and Hviid's large-scale Danish study that found no clear FBOE, Vilsmeier et al.'s meta-analysis that questioned the statistical validity of previous FBOE claims, and Ablaza et al.'s extensive Dutch study that found a significant effect of older siblings (both brothers and sisters) on homosexuality. Scott concludes that while the FBOE hypothesis has been forced to evolve, the core idea that more older siblings increases the likelihood of homosexuality seems to stand, though the biological mechanism remains uncertain. Shorter summary

Scott Alexander rebuts Bryan Caplan's arguments about mental illness, criticizing the preference/constraint dichotomy and providing counterarguments to Caplan's claims. Longer summary

Scott Alexander responds to Bryan Caplan's latest arguments about mental illness, criticizing Caplan's preference/constraint dichotomy and his claim that mental illnesses are just voluntary preferences. Scott argues that the distinction between preferences and constraints is not clear-cut, and that both physical and mental illnesses involve a mix of the two. He provides several counterarguments, including examples from physical illnesses, gradients of ability, and cases where the 'gun to the head' test fails. Scott also discusses how the framing of conditions as preferences or constraints depends on factors like ease of satisfaction and social norms. He concludes by rejecting Caplan's argument that one must either deny mental illness exists or classify homosexuality as a mental illness. Shorter summary

Scott Alexander argues that a purely biological, apolitical taxonomy of mental disorders is impossible due to ethical and practical considerations that inevitably influence classifications. Longer summary

Scott Alexander discusses the limitations of creating a purely biological, apolitical taxonomy of mental disorders. He argues that such a taxonomy is inherently impossible because the classification of mental disorders is not just a scientific issue, but also a practical and ethical one. Using examples like transgender identity, homosexuality, and pedophilia, he demonstrates how biological similarities can conflict with ethical and practical considerations in classification. The post highlights the tension between scientific accuracy, stigma avoidance, and ensuring access to necessary care. Scott concludes that new taxonomies like HiTOP are still useful, but claims of avoiding political bias in disorder classification are unrealistic. 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 Alexander examines how the 'typical mind fallacy' might lead some closeted gay individuals to support anti-gay positions, potentially influencing broader anti-gay arguments. Longer summary

Scott Alexander explores the concept of 'typical mind fallacy' in relation to anti-gay attitudes. He suggests that some closeted gay individuals might assume everyone is secretly gay, leading them to support anti-gay positions for reasons that make sense from their perspective. The post discusses how this mindset could logically lead to common anti-gay arguments, such as gay marriage destroying straight marriage or teaching about homosexuality turning children gay. While acknowledging this can't explain all anti-gay attitudes, Scott proposes it might have a larger impact than expected by influencing broader arguments and justifications. Shorter summary

Scott examines the concept of political tolerance, questioning where and why society draws the line between acceptable and unacceptable political views. Longer summary

Scott explores the concept of political tolerance and where society draws the line between acceptable and unacceptable political views. He discusses how certain issues like abortion, while deeply controversial, are treated as 'merely political' and don't typically result in social ostracism. In contrast, other views like anti-Semitism are considered beyond the pale. Scott ponders whether we should have a line at all, considering his own experience of befriending a neo-Nazi online. He then examines the logical implications of complete tolerance, including the uncomfortable conclusion that tolerating someone's political views should extend to tolerating their actions based on those views. The post ends with Scott considering a potential solution of tolerating political opinions and legal actions but not illegal ones, while acknowledging that his intuitions don't fully align with this logical conclusion. Shorter summary