Tolerance can be exercised only by those who have well-grounded convictions (although it will not always be exercised even by them). For such people tolerance is an act of self-abnegation; although they are convinced that those who differ from them must be wrong, they nevertheless will protect their rights.
Only a person with convictions has a genuine possibility to be tolerant. He who accepts no absolute values but clings to polite doubt cannot be tolerant but merely indifferent. He is morally defenseless in the face of evil.
Sometime in the coming century, people will rack their brains pondering how nations with tremendous scientific and intellectual achievements could have given uninstructed and untrained men and women the right to vote equally uninstructed and untrained people into responsible positions.