Friendship with the upright, with the truthful and with the well informed is beneficial. Friendship with those who flatter, with those who are meek and who compromise with principles, and with those who talk cleverly is harmful.
Because the newer methods of treatment are good, it does not follow that the old ones were bad: for if our honorable and worshipful ancestors had not recovered from their ailments, you and I would not be here today.
If the people are governed by laws and punishment is used to maintain order, they will try to avoid the punishment but have no sense of shame. If they are governed by virtue and rules of propriety are used to maintain order, they will have a sense of shame and will become good as well.
Some are born with knowledge, some derive it from study, and some acquire it only after a painful realization of their ignorance. But the knowledge being possessed, it comes to the same thing. Some study with a natural ease, some from a desire for advantages, and some by strenuous effort. But the achievement being made, it comes to the same thing.
Listen widely to remove your doubts and be careful when speaking about the rest and your mistakes will be few. See much and get rid of what is dangerous and be careful in acting on the rest and your causes for regret will be few. Speaking without fault, acting without causing regret: 'upgrading' consists in this.