Plutarch's Lives of the Noble Greeks and Romans, commonly called Parallel Lives or Plutarch's Lives, is a series of biographies of famous men, arranged in tandem to illuminate their common moral virtues or failings, written in the late 1st century. The surviving Parallel Lives comprises twenty-three pairs of biographies, each pair consisting of one Greek and one Roman, as well as four unpaired, single lives. It is a work of considerable importance, not only as a source of information about the individuals described, but also about the times in which they lived.As he explains in the first paragraph of his Life of Alexander, Plutarch was not concerned with writing histories, but with exploring the influence of character, good or bad, on the lives and destinies of famous men. He wished to prove that the more remote past of Greece could show its men of action and achievement as well as the nearer, and therefore more impressive, past of Rome. His interest was primarily ethical, although the lives have significant historical value as well. The Lives was published by Plutarch late in his life after his return to Chaeronea and, if one may judge from the long lists of authorities given, it must have taken many years to compile.