I don't know about the '74 figure, but the WHO only stoped classifying homosexuality as a mental illness in 93. Scary.
It is also hard though, to think openly, and not judge anyone. Some girl walks past me in college with dyed hair and a stupid outfit, my first thought is 'thick****.' She might be smarter than me for all I know, but I can't help making that judgement. Everyone does it, and yet most people get so uptight when other people do it.
And I will admit, put me in a room with a chinese guy and a black guy, I tend to feel more threatened by the black guy. Why? No idea. Never had a bad incident with a black guy. I rationalise and don't let the first set of thoughts that pop up override everything- its easy enough to tell yourself not to be so dumb, but nobody is 100% open minded and non-judgemental.
Am I mentally ill for not shaving and looking down on women who are slaves to fashion and diets? Is my mother mentally ill for having a passion for swords and pirate corsets?