"To illustrate entropy increase, take a glass jar and fill it up a quarter of the way with salt. Then add granulated pepper until it is half full. There is a black layer on top of a white layer -- an improbable configuration of all the particles. This configuration has relatively low entropy because is its highly organized and not messy. Now shake the jar vigorously. The result is a gray mixture, a disorganized configuration of the salt and pepper. If you keep shaking it is very unlikely that the original configuration will ever return. Not in a million years of shaking will it return. The entropy or disorganization of the system has permanently increased. This illustrates the second law of thermodynamics: For any closed system the entropy always increases. A system will always change from a less probable configuration (black pepper on top of white salt) to a more probable configuration (gray mixture). It is important that the system be closed for the law of entropy increase to apply., If I open the jar of the gray mixture and carefully separate the salt and pepper I can recreate the original configuration.
"When I was a college freshman my roommate and I decided we were tired of cleaning up the single room we shared and allowed it to go to a state of "maximum entropy." The room became a complete mess, much to our satisfaction. If we moved anything we couldn't help cleaning it up, but the next move would recreate the mess. The cleaning problem was solved, but another problem arose -- we couldn't find anything. Several minutes would be spent looking for the things we needed. Eventually we decided the state of maximum entropy was not saving us time and effort and we returned to a more conventional life-style.
"The law of entropy increase is manifested all about us. The phenomenon of material deterioration is an example. Everything eventually falls apart -- buildings crumble and fall into ruin; we age; fruit rots...."
