Probabilist

(n.) One who maintains that certainty is impossible, and that probability alone is to govern our faith and actions.

Probabilist - Other Definitions

(n.) One who maintains that certainty is impossible, and that probability alone is to govern our faith and actions.
(n.) One who maintains that a man may do that which has a probability of being right, or which is inculcated by teachers of authority, although other opinions may seem to him still more probable.