I really feel I am on the appropriate forum for this one (warning; weird question follows):
When hearing a major scale, most people associate upbeat feelings to it. The same way, most people attach melancholy or sorrow to minor scales.
When hearing a diminished fifth interval, one tends to think of it as rather unstable.
Whole tone/Lydian (etc.) scales is related to dreamy topics.
Now, WHO decided that the mentioned associations go with the given scales/sounds/tonalities? When was it agreed that: "Yes, this type of sound is associated with happiness, because..." - What is it that makes it happy?
I know this is an extremely mental question, and I'll see if it gets any replies. I might return with more accurate information/specified questions soon. I just find the subject quite interesting. WHO said that "this scale suits (insert 'state of mind' here)"? Why isn't diminished intervals considered "upbeat"?
Very strange question - I know, I know - but I have thought about this several times.