As mankind began to develop more complex ways of life, and as cities began to increase in size and complexity, a new type of society emerged. These societies are known today as civilizations. A civilization is a nation or people that share a common culture, common laws, a common economy, and typically a common faith or religion.
A long habit of not thinking a thing wrong gives it a superficial appearance of being right.
In the Middle Ages people believed the teachings of Aristotle, that the heart was the seat of intelligence.