[Dylan16807]

If you expect that X will make you happy, and do X, most people will report being happier for a while. That's true no matter what X is. It could even be frowning, let's say "to use up the negative emotions" or whatever. That by itself is not evidence that X does anything.

[galaxia2]

I understand where you're coming from. It's a form of confirmation bias. But for me as long as it works for me I'm fine with it. Scientific results be damned. Science serves man, not the other way around.

[Dylan16807]

If you have something that works for you, great. But don't confuse that with the actual question the study is trying to ask, which is knowledge about how emotions work. The result doesn't tell you what to do, but it's irrelevant to what you do. Don't damn it, just leave it to the people that are interested in that question for other reasons.

[dkersten]

The placebo effect is a real thing that actually has benefits. In this particular case, even if smiling is purely placebo, all is well because a smile is free (of charge and of adverse side effects).

But in the case of many medicines, just because magic-miracle-pill-x "works for you" doesn't really mean its a good idea if it actually only works due to placebo: maybe its really expensive (for something that may as well be just sugar) or maybe there is actual medication that is much more effective or maybe its safety hasn't been fully studied as is the case with much alternative medicine.

In any case, Hitchens's razor applies:

    What can be asserted without evidence can be dismissed without evidence.