What always fascinated me about the sculpture is the placement of the Thinker above the door. I suppose his presence could signify how any attempt to replace the divine Word with human understanding is doomed to hell-fire and torment.
I would suggest an alternative interpretation. Perhaps the Thinker is actually an accountant; hell seems like an apt place for most of that ilk (sorry Heiffer). Moreover, perhaps his punishment is not to sit on a stool with poor lumbar support. Instead his punishment is to spend eternity contemplating the U.S. Tax Code. I can think of no worse torment.
Now back to my Federal Income Tax homework. May God have mercy on my soul.