perfectibilist
(pəˈfɛktɪbɪlɪst) or perfectibilian
n (Philosophy) philosophy (predominantly in relation to the Illuminati) a person who believes that a given thing, usually human nature, is perfectible
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014