The diary entry discusses how much the world has changed over the writer's lifetime due to discoveries in humanism, science, and knowledge. The writer believes Petrarch has had the biggest impact by starting the Renaissance and teaching that the world is not just about God, allowing other thinkers and inventors like Da Vinci, Galileo, and Gutenberg to contribute. Petrarch challenged the absolute power of the Church and Pope, giving people more freedom to investigate and learn.