The Gudjonsson Suggestibility Scale (GSS) is a tool that helps psychologists measure how suggestible someone is. It works by asking a person questions and then analyzing their responses. The questions are designed to measure how easily a person will take on someone else's idea, change their opinion based on that idea, and then stick to it. By looking at a person's responses to the questions, psychologists can get an idea of how easily that person will accept and be influenced by what other people say.