Sophist :  (noun)
1: any of a group of Greek philosophers and teachers in the 5th century BC who speculated on a wide range of subjects [syn: Sophist]
2: someone whose reasoning is subtle and often specious [syn: casuist]

Jesuit, casuist, choplogic, cosmologist, dialectician, logicaster, logician, logistician, metaphysician, paralogist, philosophaster, philosophe, philosopher, philosophizer, ratiocinator, rationalist, rationalizer, reasoner, sophister, speculator, syllogist, syllogizer, thinker,