It is scientifically proven that with incentives there is an increase in motivation to do something- this is called the Drive Theory.
Sheldon and Raj discuss the pros and cons of getting tenured at the university.
Kramer, George, Jerry, and Elaine sit by and watch while a man is carjacked. They are arrested for not acting under the town's new Good Samaritan law. The law is designed to overcome individuals' incentive not to come to others' rescue; we can think of this as a law that changes payoffs in a game matrix.
George asks Lupe, the maid at his hotel, to untuck the sheets at the foot of his bed, because he can't sleep if the sheets are too tight, George is disappointed in Lupe, who didn't untuck his sheets as she had promised. Jerry asks George if he remembered to tip Lupe, but George forgot (no incentive after you're gone and if you're not coming back). Jerry says, "That's why communism failed."
Sonny finds a creative way to get Julian to take a bath by dressing up as Scuba Steve, Julian's favorite action man. Sonny incentivizes Julian by suggesting he can be part of the Scuba Squad if he takes care of his responsibilities. Sonny demonstrates heuristic problem solving by using his prior knowledge of Julian to solve the problem.