In the far distant future, in the year 4527, a number of scientists from all over the universe were having a convention on a far distant galaxy. Two beings were seated next to one another when they struck up a conversation.
"Where are you from?" the one asked.
"I'm from Alpha Century," he answered. "Where are you from?"
"I'm from Earth," was the answer.
"I know someone from earth," the Alpha Centurion said. "His name is John Smith. Do you know him?"
At a girl's college dormitory, dates were permitted only on Saturday night. One young man showed up on a Tuesday evening, explaining to an older woman in the lobby of the dorm that it was imperative he see a certain young lady immediately.
"I want to surprise her. You see, I'm her brother."
"Oh, she'll be surprised all right," said the woman. "But think of how surprised I am, I'm her mother!"