High Quality Content by WIKIPEDIA articles! In the philosophy of thermal and statistical physics, Maxwell`s demon is a thought experiment created by the physicist James Clerk Maxwell to "show that the Second Law of Thermodynamics has only a statistical certainty". It demonstrates Maxwell`s point by hypothetically describing how to violate the Second Law: a container is divided into two parts by an insulated wall, with a door that can be opened and closed by what came to be called "Maxwell`s demon". The demon opens the door to allow only the "hot" molecules of gas to flow through to a favoured side of the chamber, causing that side to gradually heat up while the other side cools down, thus decreasing entropy.