Once you do away with the idea of people as fixed, static entities, then you see that people can change, and there is hope.

This quote means that if you stop viewing other people as unchanging and set in their ways, you will realize that people can transform themselves, and this gives one hope. People are not only capable of change, but it can also bring optimism about the future. If people are not seen as stagnant, then their potential for growth and improvement is on display. This encourages a person to have hope for a better tomorrow.