With the conquests of the Caliphates, the Muslims managed to take control over multiple regions. One of those regions was North Africa, where in Egypt, in the city of Alexandria there were millions of books with scientific and philosophical themes. It was the center of knowledge of the world in that time.
The Muslims unfortunately destroyed most of the books from the antiquity, and only few were preserved. Thus few though got into the hands of Muslim scholars that were interested in science and philosophy. They read them carefully and started to base their researches on them, making significant progress and discovering multiple things. By preserving these few books, and also upgrading on their basis, helped to preserve at least some part of the ancient knowledge, which later was reintroduced in its place of origin, Europe.
Although the Greek city states all spoke the same language and worshipped the same gods, each polis had their own government systems and values. Athens and Sparta, in particular had opposing values; Athens had a democracy, Sparta had a monarchy, where Athenians prized new ideas, the Spartans stubbornly clung on to the traditional etc. Partially due to Pericles taking advantage of the Delian League to benefit Athens, other city states began to resent Athens and eventually the Greek city states sided with either Sparta or Athens in the Peloponnesian War.
George Washington did not want to accept the presidency that the people wanted to give him for fear of becoming a tyrant himself, just like King George II of England, from whom they just declared themselves independent from. When he became president, he made an example by only taking 2 terms and then refusing to continue being president. It wasn't until much later that a law was introduced to prevent any single president from serving more than 2 terms.
