John Green discusses the strange and mutually beneficial relationship between a republic, the city-state of Venice, and an Empire, the Ottomans--and how studying history can help you to be a better boyfriend and/or girlfriend. Together, the Ottoman Empire and Venice grew wealthy by facilitating trade: The Venetians had ships and nautical expertise; the Ottomans had access to many of the most valuable goods in the world, especially pepper and grain. Working together across cultural and religious divides, they both become very rich, and the Ottomans became one of the most powerful political entities in the world. We also discuss how economic realities can overcome religious and political differences (in this case between Muslims and Christians), the doges of Venice, the sultans of the Ottoman empire, the janissaries and so-called slave aristocracy of the Ottoman Empire, and how money and knowledge from the Islamic world helped fuel and fund the European Renaissance. Also, there's a They Might Be Giants joke.