The best fitness advice you've ever received was probably wrong — not because it was false, but because it was someone else's solution encoded as a universal rule. William James, in his 1890 Principles of Psychology, made a distinction that most tip-culture ignores: the difference between a generalization derived from aggregated experience and a working hypothesis derived from personal experimentation. A tip is always the former. It was true for whoever generated it, under conditions you didn't share, in a body you don't have. James's point wasn't that generalized knowledge is useless — it's that it's inert until you've run it against your own case. The fitness tip about morning fasted cardio, the chiropractic growth hack about re-activation campaigns, the staff meeting structure someone swears by — each is a data point, not a directive. The concrete move: next time you encounter a tip that 'should' work, write down the specific conditions under which it was generated versus the conditions of your actual life. Where they diverge is where you stop copying and start experimenting.

What is a fitness or practice tip you've been applying for months that you have never actually tested against your own data — and what would you need to measure to know if it's working for you specifically?

Drawing from American Pragmatism — William James (Principles of Psychology, 1890)