Benjamin Franklin was, in my opinion, one of the most interesting people in history. He was a true polymath and genius. His accomplishments in science, literature, foreign diplomacy, politics, music and a host of other fields are many.
One of the interesting principles he followed is he avoided directly criticizing people as much as possible. Also, he had a way to make friends wherein whenever he met a new person he wanted to be friends with, he sought their help in some matter. Once the person had helped him, he thanked them well and so forged a friendship. As a result, he was able to gain the friendships of many people all over the world.
In his autobiography, he listed thirteen virtues he considered most important:
Following these virtues undoubtedly helped him to live a long and happy life. He was the richest man in the country for a long time. His bequest to his beloved city of Philadelphia where he established, among other things, one of the first firefighting and library companies, had grown with the accumulation of compound interest, and was used to establish what is today the Benjamin Franklin Institute of Technology.