In chapters 4 and 5, Harry becomes fabulously wealthy and meets Draco Malfoy. Anthea, Elisa, and Jake are joined by Ernie to discuss effective altruism, the fundamental attribution error, and being built different. Citations and further reading: Harry Potter and the Methods of Rationality, chapter 4: https://hpmor.com/chapter/4HPMoR, chapter 5: https://hpmor.com/chapter/5"Eliezer's Unteachable Methods of Sanity," Eliezer Yudkowsky. LessWrong, 6 Dec 2025. https://www.lesswrong.com/posts/isSBwfgRY6zD6mycc/eliezer-s-unteachable-methods-of-sanity"ELI5: What is arbitrage and how do arbitrageurs make money?" r/explainlikeimfive, 27 Nov 2012. https://www.reddit.com/r/explainlikeimfive/comments/13wekw/comment/c77s5go/"Effective Altruism." Lesswrong, 2 May 2024. https://www.lesswrong.com/w/effective-altruism"Purchase Fuzzies and Utilons Separately," EY. LessWrong, 1 Apr 2009. https://www.lesswrong.com/posts/3p3CYauiX8oLjmwRF/purchase-fuzzies-and-utilons-separately"Can one person make a difference? What the evidence says." Benjamin Todd. 80,000 Hours, accessed 22 Apr 2026. https://web.archive.org/web/20260219151243/https://80000hours.org/career-guide/can-one-person-make-a-difference/"Sam Bankman-Fried on Arbitrage and Altruism (Ep. 145)," Conversations With Tyler. 9 Mar 2022. https://conversationswithtyler.com/episodes/sam-bankman-fried/"An excellent collection of Fermi problems for your class," Kevin Cummins. Innovative Teaching Ideas, 14 Aug 2023. https://innovativeteachingideas.com/blog/an-excellent-collection-of-fermi-problems-for-your-class/"Fundamental Attribution Error." Wikipedia, accessed 22 Apr 2026. https://web.archive.org/web/20260401065702/https://en.wikipedia.org/wiki/Fundamental_attribution_error"Fundamental Attribution Error in Psychology," Saul McLeod. SimplyPsychology.com, accessed 22 Apr 2026. https://www.simplypsychology.org/fundamental-attribution.html"The attribution of attitudes," Jones and Harris. Journal of Experimental Social Psychology, January 1967. https://www.sciencedirect.com/science/article/abs/pii/0022103167900340?via%3Dihub"The "Fundamental Attribution Error" is rational in an uncertain world," Walker, Smith, and Vul. Proceedings of the Annual Meeting of the Cognitive Science Society, 2015. https://escholarship.org/uc/item/48d9b5qb#main"Don't Revere The Bearer Of Good Info," CarlShulman. LessWrong, 21 Mar 2009. https://www.lesswrong.com/posts/tSgcorrgBnrCH8nL3/don-t-revere-the-bearer-of-good-info