In 2012, after a months long program of hard exercise (lots of intense jump/plyometric training) my left foot started to really hurt and be constantly tight on the underside. Podiatrist diagnosed Plantar Fasciitis, and prescribed anti-inflammatory meds + foot taping to relieve the pain walking. There was clearly a physical cause for the pain, and I had obviously over done things. But after ~3 months of taping my feet every day, and dosing on naproxen (stiff stuff), my foot was now intermittently better. It would soften up and feel fine one day, or in the evening, but then totally flare up the next day. I now know that 3 months is more than enough time for such an overuse injury to physically heal, but even at that time in 2012 I suspected that it was bogus and kept thinking “this is bullshit!” Thankfully I was a Howard Stern fan, and recalled how he periodically talked up Dr Sarno and the great help he provided. So I got one of the books, and within a couple weeks of “thinking my way out of it”, my feet were just fine.