The Think System is based on the idea that music is a language, and that anyone can learn to read and understand it, just as they would learn to read and understand a spoken language. Hill's system uses a series of charts and diagrams to teach students the basic elements of music, such as rhythm, melody, and harmony. He also uses a system of hand signals to help students learn how to play their instruments.
While the Think System is presented as a legitimate method of teaching music in the musical, it is actually a scam. Hill is not a real music teacher, and his system does not actually work. However, he is able to convince the people of River City, Iowa, that he is a legitimate musician, and they pay him a large sum of money for his services.
The Think System is a satirical take on the many get-rich-quick schemes that were popular in the early 20th century. It is also a commentary on the power of persuasion and the gullibility of the public.