Rationality: From AI to Zombies - Eliezer Yudkowsky. Intro to rationality, divided into 6 books. Especially the chapters on Twelve Virtues of Rationality, My Bayesian Enlightenment, Raising the Sanity Waterline, Three Levels of Rationality Verification, When Not To Use Rationality, The Real Prisoner’s Dilemma, Rationalists vs Barbarians, Church vs Task Force, Can Humanism Match Religious Output, Why Our Kind Can’t Cooperate. See Heuristics & Biases for a shorter talk by Yudkowsky or Harry Potter And The Methods of Rationality for a fan-fictional account of rationality.
LessWrong - an online community dedicated to improving human reasoning and decision-making. A Map That Reflects The Territory - Lesswrong book series on epistemology, agency, coordination, curiosity, and alignment.
Gwern, Overcoming Bias, Second Enumerations, Ribbonfarm, Nintil, MeltingAsphalt and especially AstralCodexTen are blogs that apply rational thinking to a plethora of long-termist topics. In podcast form, Rationally Speaking has excellent rationalist interviews with a range of thinkers. Graph Of The AXC Blogosphere - Jacob Wood. An overview of AXC- related blogs to get a sense of the space.
Cognitive Biases in Catastrophic Risks Map - Alexey Turchin. How our biases can influence how we make sense of crucial risks to humanity. Other compilations of biases include List of Biases by Rationalwiki and the Cognitive Bias Codex poster.
Incerto: Fooled by Randomness - Nassim Taleb. The whole collection is worth reading.
Thinking Fast & Slow - Daniel Kahneman. A classic contrasting fast, instinctive, heuristic thinking with slow, reasoned thought, including when we use which one.
Tools to Transform Our Thinking - Daniel Dennett, A talk on how to get better at reasoning, including popular methods such as the “intuition pump”.
Arguably - Christopher Hitchens. An essay collection.
Superforecasting - Philip Tetlock. Why we are bad at forecasting and how to get better. For more tips, see The Art of Predicting, a podcast with Anthony Aguirre and Andrew Critch, and Tetlock on Predicting, a podcast with Robert Wiblin and Philip Tetlock.
Metaculus - A community forecasting platform working to improve human decision-making and coordination on topics of global importance through a process of collective reasoning and aggregated prediction. Other projects that actively try to improve our ability to predict, forecast and estimate include Good Judgment and Guesstimate.
Prediction, Replication, Decision Markets - Foresight Institute. Interview with Robin Hanson, Chis Hibbert, Anthony Aguirre and other prediction market builders on various versions of prediction markets.
Clearerthinking.org - Offers mini-courses and provides tools using research about human behavior to improve our decision-making.
Recommended Rationalist Reading - Eliezer Yudkowsky. Collection of rationalist resources.
Rational Choice in an Uncertain World - Reid Hastie, Robin Dawes. Coursework-style info on how to update your thinking. Similarly extensive resources on rationality include Probability Theory: The Logic of Science by E.T. Jaynes, and Street-Fighting Mathematics: The Art of Educated Guessing and Opportunistic Problem Solving (dropbox).