How do you judge if someone is stupid?

Stupid people are genetically wired to be stupid. They will be that way all their life. Don't confuse ignorant people with those who are stupid: ignorant people simply haven't learned but are capable of doing so; stupid people are incapable of learning a great deal of things. When you consider that half of all people have an IQ less than 100, and some considerably less, you come to realize that on average, every other person you deal with is verging on stupidity.