Here are three books with the same fundamental substance: Vedanta, 7 habits, Flow. But there's huge variation in the form. Vedanta, written in antiquity, states the truth baldly in dictums. 7 habits, from the late 80s, avoids putting the reader off by phrasing its dictums as choices. Flow synthesizes cognitive research to describe how the changes we make within ourselves lead to external improvements. That's an appealing formulation to me after 20 years of the self-help cliches spawned by 7 habits.

These books exemplify a trend: knowledge gets progressively more accessible, not just by ubiquity but by the form in which it's consumed. When knowledge was scarce readers were supplicants, happy to take it in any form. Now it is abundant, writing is a buyer's market with greater emphasis on form. The filters readers create—against the preachy, against cliches—coevolve with the gimmicks of sellers and the skill of writers.

Credit: conversations with dad