Fanatical dogmatism, which is one of the great evils of our time, is primarily an intellectual defect and, as I suggested before, it is one to which philosophy supplies an intellectual antidote. But a great deal of dogmatism has also an emotional source: namely, fear. It is felt that only the closest social unity is adequate to meet the enemy and that the slightest deviation from orthodoxy will have a weakening effect in war. Frightened populations are intolerant populations
Source: Bertrand Russell: A Philosophy of Our Time (1953)
More info.:http://russell-j.com/beginner/1026_PfOT-060.HTM