Fill the containers with gases, and placea  microscopic creature at the door, with orders to let only hot molecules pass  into one container and only cold molecules in to the other.
Take two closed containers separated by an adiabatic wall with a  microscopic trap door. Fill the containers with gases, and placea  microscopic creature at the door, with orders to let only hot molecules pass  into one container and only cold molecules in to the other. The result will  be a system in which the entropy as a wholedecreases. FTP, name the creature  and you will name this thought experiment designed to violate the second law  of thermodynamics.
Take two closed containers separated by an adiabatic wall with a  microscopic trap door.
{Maxwell's demon}