The Shopping Cart Theory originated as an anonymous text post that gained viral status on sites like 4chan and Reddit, eventually becoming a staple of internet philosophy. It argues that returning a shopping cart is the ultimate litmus test for whether a person is a good or bad member of society because there is no legal requirement to do so and no reward for doing it; it is simply the 'right thing to do.' The theory suggests that an individual who is incapable of performing this small, selfless act without being forced is an 'animal' who only obeys the law because of the threat of punishment. The meme is used widely to spark philosophical debates, judge the behavior of others, and comment on the perceived breakdown of the social contract in modern society.