Particle Physics -recent Succeaaea and Future Prospects'

The situation in particle physics today is highly analogous to that which existed in chemistry towards the end pf the 19th century. During the preceding two centuries, remarkable progress has been achieved in that discipline, progress that culminated in the periodic table of Mendeleyev. This table summarieed not only the realieation that our everyday matter is composed of basic building blocks, called elements, but also that these different elements had certain similarities which could be used to properly arrange them in the periodic table. Thus the inert gases (helium, neon, argon, etc.) had very similar chemical properties, namely chemical inertness; the halogens (chlorine, iodine, florine) on the bthephand were highly reactive. Other similarities were seen among the rare earth group of elements, alkaline earths, and alkali metals. What was missing, however, was a deep understanding of the reason for these regularities.