"Reductionism 101" is the a sequence of essays (assigned letter P) in Mere Reality, volume four of the Rationality: From AI to Zombies ebook. These were originally posts on Overcoming Bias, and the essay names below link to the original blog pages:

189. Dissolving the Question

190. Wrong Questions

191. Righting a Wrong Question

192. Mind Projection Fallacy

193. Probability is in the Mind

194. The Quotation is not the Referent

195. Qualitatively Confused

196. Think Like Reality

197. Chaotic Inversion

198. Reductionism

199. Explaining vs. Explaining Away

200. Fake Reductionism

201. Savanna Poets

The previous essay sequence is "Lawful Truth," and the next one is "Joy in the Merely Real."