First a recap for those of you who don't know the difference. An illusion is something that appears to be, but is not. For example, if you make a quarter disappear then "find" it behind someone's ear. A delusion is a mistaken belief-system. For example, believing anyone was fooled by that lame quarter trick for even a second. An allusion is a reference to an earlier famous work. For example, saying, "That stupid quarter trick of yours is even dumber than Good Soldier Svek in the eponymous novel by Hasek."
So what are some common delusions afflicting the American psyche?
1. Believing You are Always Right. This one is damn near universal at one time or another. The condition is usually treatable in males by marriage.
2. Believing Someone Else is Always Right. This is rarer than #1 although it has become somewhat more prevalent since the advent of talk radio. In marriages, this usually takes the form of one spouse believing a third party has all the keys of all knowledge. "Why don't you ask so-and-so," or "So-and-so says..." [So-and-so is used here merely as a placeholder. It is not meant to denigrate anyone with a last name that is actually So-and-so.] Believing someone else is always right is potentially dangerous if left untreated since it frequently leads to homicidal thoughts in the other spouse.
3. Believing Someone Else Believes He or She is Always Right. This one's a doozy. And really difficult to treat. Even Freud was like, "Dude." Even if the object of the delusion admits he's been wrong, this only serves, but some sort of backward logic, to confirm the delusion of the deluded party. Is that clear? Commonly in a marriage, both spouses will be afflicted with this delusion, each believing the other believes he or she is infallible while believing oneself to be freely willing to admit one's own foibles, mistakes, and short-comings. This leads us to delusion #4, which is
4. Believing You Do Not Believe You are Always Right. By now you're starting to see why psychoanalysts seem so grumpy all the time. People afflicted with #4 are frequently subject to #1 and #3 as well, and often, through a kind of neurotic contagion, their spouses are subject to the same delusions with occasional bouts of #3 thrown in because, hey. Technically, this situation is called a hot mess and it is astonishingly prevalent among married couples. For years, compassionate legislators tried to block gay marriage, hoping to spare homosexuals, who otherwise seem so happy and carefree (ie "gay") this torment, but now gays can get married, too. They can't say we didn't try to warn them. There is no cure for this combination-type delusion, and the only known treatment is to sit couples in front of the tv and make them watch endless streaming shows so they don't get an opportunity to speak to each other.
5. Believing You are a Carrot. Actually, there are no known cases of this delusion, but it'd be nice once in a while to meet someone who was willing to say, "I'm a carrot," and leave it at that.