This trope is popular in Philosophy. One such thought-experiment goes like this:
Bert is mildly retarded: He just doesn't get sarcasm. During his entire childhood he is everybody's laughingstock, but he mistakenly believe that they are laughing with him rather then at him.
- Failing to see that everyone around him is simply in it For the Evulz, he incorrectly believe that he have friends who care about him.
- As they turn adult, some of his "friends" become powerful and decide to carry on the charade. Bert now believe himself to be a respected coworker who contributes to the company, but no one really regards him as a peer. His only real function in the company is that he'll be an expendable scapegoat if something goes horribly wrong. Luckily for him, the company is lucky enough to never have to discard him.
- During a trip to a third world country, one of the "friends" befriends a prostitute. Their friendship is real, with mutual affection, and she quickly join his circle of friends who laugh at Bert behind his back. They want their new friend to get a western citizenship, and Bert becomes a convenient tool for that. And thus he gets married to a woman who doesn't care about him and never will, but who will let him believe that she does. She even let him have sex with her a few times... especially after she gets pregnant, so he will believe that the kids are his own.
- "His" children grow up to pity him, and they are grateful when they find out that the "uncle" they like so much more then him (and who their mother truly loves) is actually their real father. Of course, they are too polite to tell Bert the truth.
- As Bert lives out his life, he dies surrounded by people he believe to be his friends, a woman he believe to be his loving wife, and children he believe to be his offspring. It's all a lie, and afterwards none of them have time to go to his funeral since they happen to get invited to a party that is held the same night. He have outlived his usefulness, and nobody really miss him. On the contrary, they merely feel relieved that he can no longer embarrass them by exposing any of the stuff they used him for.
- And the question is: Did Bert live a good life?