How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence

by Michael Pollan

Robin Carhart-Harris’s theory of the entropic brain represents a promising elaboration on this general idea, and a first stab at a unified theory of mental illness that helps explain all three of the disorders we’ve examined in these pages. A happy brain is a supple and flexible brain, he believes; depression, anxiety, obsession, and the cravings of addiction are how it feels to have a brain that has become excessively rigid or fixed in its pathways and linkages—a brain with more order than is good for it. On the spectrum he lays out (in his entropic brain article) ranging from excessive order to excessive entropy, depression, addiction, and disorders of obsession all fall on the too-much-order end. (Psychosis is on the entropy end of the spectrum, which is why it probably doesn’t respond to psychedelic therapy.)