But I also believe that perfection is remarkably fleeting. The world is constantly in motion, down to the last atom. Even the atoms in a rock are in motion. The beaver builds the perfect dam, until it is washed away by a storm. Michelangelo paints the ceiling of the Sistine Chapel, but over time it begins to fade.
People change as well.
No, we are not immutable. We change, moment to moment, whether we are aware of it or not. Yes, we can. What we cannot do, what we cannot expect to do, is to sustain it. In high school, I had a terrible emotional upheaval in my life.