  The twentieth century has thrown up exotic concepts -- dark matter, gravity
waves, Higgs Bosons, Magnetic Monopoles and so on. The sad truth is that even
after several decades, these remain elusive to observation and experiment. Some
are now questioning these conjectures. Their verification has become a matter
more of hope than conviction. We will examine some alternatives in the light of
the above pointing out that, on the other hand, an extra neutrino, recently
predicted by the author may have just been discovered.
