Fear

Fear n. a distressing emotion aroused by impeding danger, evil, pain, etc., whether the threat is real or imagined; the feeling or condition of being afraid.

Many allow fear to rule their lives. Fear is comfortable, predictable, understood. Individuals may try not to pretend their fears can be controlled, but they can. Conquering fear is by no means a quick process. Time is a factor in everything one does. In all honesty, fear and pain are the two factors holding back the progression of humankind. Luckily, we don't need to know everything to survive.