It's important to bear in mind that meditation is a religious practice specifically aimed at causing ego-death. Yogis writing about the practice (before it became big business) freely admit all sorts of horrible-sounding mental side effects, but couch them in religious terms (and encourage the acolyte to push through until they achieve "enlightenment", which they describe as a profoundly nihilist state of being). Thi…
In fact there is scientific evidence that meditation and professional sports are the only activities that strengthen a person's will. I guess with sufficient motivation it's possible to find a study that claims anything.
> anti-. Scientists will hold an open mind, but "gurus" who charge money for fancy retreats will insist in its value without evidence.
I went for half a year every week to a free meditation meetup. The guy holding the meetup was the most relaxed person I have ever encountered in my life. Apparently he has has been travelling extensively to Japan and lived happily next to a Railway station. (Some people would go crazy living there with all the noises) For me he was the living proof this stuff actually works.
No need for Gurus here, although it's surely possible to get scammed like with everything. Probably one should get suspicious when the meditation is expensive or at a remote place.