Porphyry also tells us in the _Life_ that Plotinus devoted considerable attention to the stars and refuted in his writings the unwarrantable claims of the casters of horoscopes.[1342] Such passages are found in the treatises on fate and on the soul, while one of his treatises is devoted entirely to the question, “Whether the stars effect anything?”[1343] This was one of four treatises which Plotinus a little before his death sent to Porphyry, and which are regarded as rather inferior to those composed by him when in the prime of life. In the next century the astrologer, Julius Firmicus Maternus, regards Plotinus as an enemy of astrology and represents him as dying a horrible and loathsome death from gangrene.[1344] [Sidenote: The stars as signs.] As a matter of fact the criticisms made by Plotinus were not necessarily destructive to the art of astrology, but rather suggested a series of amendments by which it might be made more compatible with a Platonic view of the universe, deity, and human soul. These amendments also tended to meet Christian objections to the art. His criticisms were not new; Philo Judaeus had made similar ones over two centuries before.[1345] But the great influence of Plotinus gave added emphasis to these criticisms. For instance, the point made by him several times that the motion of the stars “does not cause everything but signifies the future concerning each”[1346] man and thing, is noted by Macrobius both in the _Saturnalia_[1347] and the _Dream of Scipio_;[1348] while in the twelfth century John of Salisbury, arguing against astrology, fears that its devotees will take refuge in the authority of Plotinus and say that they detract nothing from the Creator’s power, since He established once for all an unalterable natural law and disposed all future events as He foresaw them. Thus the stars are merely His instruments.[1349] [Sidenote: The divine star-souls.] But let us see what Plotinus says himself rather than what others took to be his meaning. Like Plato, who regarded the stars as happy, divine, and eternal animals, Plotinus not only believes that the stars have souls but that their intellectual processes are far above the frailties of the human mind and nearer the omniscience of the world-soul. Memory, for example, is of no use to them,[1350] nor do they hear the prayers which men address to them.[1351] Plotinus often calls them gods. They are, however, parts of the universe, subordinate to the world-soul, and they cannot alter the fundamental principles of the universe, nor deprive other beings of their individuality, although they are able to make other beings better or worse.[1352] [Sidenote: How do the stars cause and signify?]