Empedocles (c. 490 – c. 430 BCE) too has ascribed to him marvelous powers associated with later magicians: that is, he is able to heal the sick, rejuvenate the old, influence the weather and summon the dead. E.R. Dodds in his 1951 book, "The Greeks and the Irrational", argued that Empedocles was a combination of poet, magus, teacher, and scientist. Dodds argued that since much of the acquired knowledge of individuals like Pythagoras or Empedocles was somewhat mysterious even to those with a rudimentary education, it might be associated with magic or at least with the learning of a Magus.