All classifications in this world lack sharp boundaries, and all transitions are gradual.
Aleksandr SolzhenitsynOur Twentieth Century has proved to be more cruel than preceding centuries, and the first fifty years have not erased all its horrors. Our world is rent asunder by those same old cave-age emotions of greed, envy, lack of control, mutual hostility which have picked up in passing respectable pseudonyms like class struggle, radical conflict, struggle of the masses, trade-union disputes.
Aleksandr Solzhenitsyn