Bertie Wooster: I mean to say, I know perfectly well that I've got, roughly speaking, half the amount of brain a normal bloke ought to possess. And when a girl comes along who has about twice the regular allowance, she too often makes a bee line for me with the love light in her eyes. I don't know how to account for it, but it is so.
Jeeves: It may be Nature's provision for maintaining the balance of the species, sir.
We complement each other perfectly, Luke, all the way down the line. In many ways, we're two halves of a single being.
Manny: [referring to Ellie and her bizarre antics] So, you think she's the girl for me?
Sid: Oh, yeah. She's tons of fun, and you're no fun at all. She... completes you.
— Ice Age 2: The Meltdown
...Fours and Sevens bring to their relationship the charge and mystery of their differences—that they think so differently, react so differently, and find pleasure in such different ways. They can therefore become intrigued by the other, finding him or her endlessly fascinating, always ready with something new and unexpected.
— The Enneagram Institute's description of how Fours and Sevens might theoretically influence each other