First, one might encounter a scenario in which one's proposed maxim would become impossible in a world in which it is universalized. For example, suppose a person in need of money makes it his or her maxim to attain a loan by making a false promise to pay it back. If everyone followed this principle, nobody would trust another person when he or she made a promise, and the institution of promise-making would be destroyed. However, the maxim of making a false promise in order to attain a loan relies on the very institution of promise-making that universalizing this maxim destroys. Kant calls this a "contradiction in conception" because it is impossible to conceive of the maxim being universalized.