An antagonist is someone who opposes the main character in a piece of writing. Galileo identifies multiple antagonists in his letter and devotes much of his writing to dismantling their arguments. These antagonists include people who directly oppose his ideas and people who don’t understand them. Galileo attacks them to create a common enemy for himself and the church.

Hyperbole is exaggerated language that overstates something for effect. Galileo scatters hyperbole throughout the “Letter” to show how serious he is about his piety and to garner sympathy from his readers. For example, he says that if his work is not useful to the church, “let my book be torn and burnt, as I neither intend nor pretend to gain from it any fruit that is not pious and Catholic” (Paragraph 5). Galileo saying “let my book be torn and burnt” is hyperbole. He doesn’t truly mean this, but he says it to show how much he cares about being of use to the church.

Galileo returns to the same two ideas throughout his “Letter”: his detractors care about their reputations and don’t understand the Bible, and the Bible does not contradict heliocentrism.