I am just a little mad, mostly nuts. I like to think that most sane people are. The only way to know whether you're absolutely insane or not, is to look at whether you say you're sane or not.
For most insane people like to pretend that they are sane. Now, we all know that that's a lie.
So, I have a little challenge for you. Yes, you, whoever is reading this.
Go down the street and yell, as loud as you can "I am sane!". Now tell me, was there anyone who looked at you as if you actually were sane, no I reccon.
Now try the same thing only instead of yelling that you are sane yell that you are not sane. 
See, now so many people will look at you in a different way.
Stating the fact that you are sane, will only prove the opposite, as others may see it as completely mad.
Yelling "I am sane!" Is exactly the thing an insane serial killer would do.
Therefore please don't go around yelling "I am sane!" in a busy street, an innocent paserby might alarm the police and you'll find yourself spending the night in jail.