By luxury, we mean a pleasant and often expensive thingthat is not necessary. From a historical point of view, things which Werea luxury when they first came into being all became necessities later. When theelectric bulb was first invented in the U.S., it was such a luxury that onlygovernment bodies could afford to use it. Nowadays, however, it has reachedevery part of the world. It is the same case with telephone, TV, and a lot ofothers, which were all luxuries years ago.

　　Anything, no matter how luxurious it is, will become a necessity when itis widely used. This is true of many of the present luxuries, including mobilephones, cars, computers and many other things. It is known to all that thepurpose of the development of science is to make things easy for the mankind,not for only a small number of people. Therefore, the first thing to do after anew invention occurs is to spread it so as to benefit as many people aspossible. In the course of the spread, the luxury becomes decreasingly luxuriousuntil in the end it becomes a necessity. This is an objective law, nothing canbe an exception.

　　With the quick development of science and technology, the process formany things to become a necessity from a luxury will be greatly shortened.Anything that can be imagined will be invented and in no time becomes anecessity accessible to ordinary people.