So we have, let's say, six units of energy on this side. Now, what about the amount of energy on this side? Well, we have no molecules on this side, so we have zero units of energy. And what that means is all that energy is concentrated on the left side and no energy is found on the right side inside our system. Now, as soon as we remove this artificial barrier, as soon as we open up that door, what exactly will begin to take place? Well, what the second law of thermodynamics tells us is whenever a system is given a chance to, or whenever something is given a chance to, it will always try to become as random as possible.