Scott Alexander critiques a meta-analysis supporting psychic phenomena to illustrate flaws in scientific methodology and meta-analysis. Longer summary

Scott Alexander examines a meta-analysis by Daryl Bem that claims to provide strong evidence for psychic phenomena (psi). While Bem's analysis follows many best practices for scientific rigor, Alexander argues it likely suffers from experimenter effects and other biases that can produce false positive results. He uses this to illustrate broader issues with the scientific method and meta-analysis, concluding that even seemingly rigorous studies and meta-analyses can produce incorrect conclusions. This challenges the idea that scientific consensus and meta-analysis are the highest forms of evidence. Shorter summary