"compel each other" is a grammatically correct and usable phrase in written English.
It can be used in situations where two or more individuals are strongly influencing or motivating each other to do something. Example: The two friends had made a pact to compel each other to stick to their healthy habits, no matter what temptations came their way.
If American Ninja Warrior is about ordinary people doing extraordinary things, then Spartan is about a bunch of ordinary people compelling each other to greatness.
Efforts at compromise broke down during the spring of 1650 as the Hollanders and William each sought to compel the other to concede political inferiority.
In addition, key holders are compelled to trust each other unconditionally to protect the keys in their possession and not to misuse them.
Furthermore, the ICC's ten member nations would no longer be compelled to play each other home and away at least once in every four-year cycle, as they currently are under an agreement called the Future Tours Programme.
While BMW and Audi feel compelled to fight each other over technical prowess, regardless of whether the driver can actually take advantage of the gadgets in the car, Mercedes hasn't made it impossible to do what you need to as a driver by entirely bypassing the latest whizbang, Silicon Valley notions of "optimized interfaces".
In philosophy, especially analytic philosophy, there's this idea that if you have a powerful-enough argument, you can just compel the other person to agree.
In this case, he said, "Michigan and the federal government are on equal constitutional footing, and neither has any power to compel the other".
Will Obama be able to capitalize on these policy initiatives and compel the other leaders -- and the media -- to highlight their relevance?
If so, would this create a normative standard that would compel other former colonial powers to aid their former colonies when in need?
