Stupidity

What does one mean by the concept of stupidity? There are many different ways of looking at this concept and does it need approaching for one? When we think of something or someone as "stupid," why do we use an adjective with such a diverse meaning? Stupidity also enrages others who supposedly know better, but is it the behaviour of others that angers them, or the realisation that they too could have made the similar mistakes? When correcting others, how people go about it can reflect upon their own piece-of-mind.

I return to my original question of what stupidity actually is, as this is something I have never mused about before. I am just one of the masses who have called something or someone stupid. I have never taken time to concider what I may mean by this. Some people may think I am very rude (and for the record, I am not saying your wrong,) but isn't the concept of rude a lot similar to the concept of stupid. What one person thinks is stupid may not be an opinion shared by others, or some people may select an "offence" and typify it as stupid, but bje extremely gulity of it themselves.

One thing that I know I do and can't stand to watch/listen to others do is overstate things. Like they think the person they're talking to can't understand them. Where do they get off being so egotistical? Another thing is when people take a specifc stand point, but then go against it. For example, when Mrs Banks in Mary Poppins was campagining for women's right to vote and then she turns round to the maid and tells her to hide her sash because it make her husband mad. God I'm glad the feminists of the 1960's weren't so fickle.