Earlier quoted context omitted.
> I can say from my own experience that the lack of vitamin D can have a significant impact on both mind and body. No you can't. That's not how this works.
> No you can't. Yes I can :D While my experience is obviously not definitive scientific proof it can still bring some value. To give you a more simple example: when I broke my leg I went to the doctor's and put it in a cast. That helped me tremendously. Is that a well designed randomized controlled trial? No. Is it good advice to anybody with a broken leg? I would say so.
Me: "You can't say that."
Philosopher: "I just did."
Remainder of students: laughter