If you ask a member of this generation two simple questions: ''How do you want the world to be in fifty years?'' and ''What do you want your life to be like five years from now?'' the answers are quite often preceded by ''Provided there is still a world'' and ''Provided I am still alive.'' To the often-heard question, Who are they, this new generation? one is tempted to answer, Those who hear the ticking. And to the other question, Who are they who utterly deny them? the answer may well be, Those who do not know, or refuse to face, things as they really are.