How could one interpret Doctor Faustus from Christopher Marlowe's play of the same name as a tragic hero?

A tragic hero is one who has both good and bad qualities, but inevitably allows their negative qualities to cause their downfall.  The literary term for this fatal flaw is “hamartia.” 

While Faustus seems to be content utilizing his newfound knowledge and power to cause havoc and amuse the upper echelons of society, he did originally have more noble intentions.  Before he obtained the power, he wanted to have spirits “fly to India for gold” and “Ransack the ocean for orient pearl” (Marlowe).  He then wanted use the money to hire mercenaries, build a wall of brass around Germany, and free them from the Prince of Parma.  Faustus also imagined he would have demons read him unknown philosophy, which could have made him a better leader and expanded his knowledge of the universe. 

Faustus also wanted to “fill the public schools with silk” (Marlowe).  This was probably figurative silk, meaning great teachers, teaching materials, and all of the knowledge he had obtained.  If it was literal silk, it would have been an expensive fabric that teachers and students in public schools would have been unaccustomed to.  Either way, Faustus’ vision was for education to be of the utmost importance.

His hamartia, however, was selfishness.  All of his noble plans went by the wayside as soon as he gained power.  He spent his 24 years with knowledge that could have ended world hunger, war, and the overreaching of the Catholic Church, but used it instead to gain favor by amusing royalty and playing practical jokes.  At one point, he turns invisible and harasses the pope at a banquet, taking his food and striking him.  If he really had a quarrel with the Catholic Church, he could have used all of his knowledge and power to put an end to it, instead of just playing practical jokes.

The renaissance view is that Faustus was heroic because he sought knowledge forbidden to men by God and the Church.  In a time when knowledge of the world and of oneself was a noble pursuit, no knowledge should have been off limits.

Since Faustus did originally have some good intentions, and sought knowledge, he could have been a hero; however, he disregarded all of the good he could have done for his personal amusement, making him a tragic hero.

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