Why do we dream?

Why do we dream, and what is the meaning of our dreams? Rolf and Joe talk about several ideas about dreaming, including a new theory by David Eagleman called the "defensive activation theory", which proposes that dreams are like a screen saver to keep the visual parts of the brain from being overtaken by other senses. Eagleman, D. M., & Vaughn, D. A. (2020). The Defensive Activation theory: dreaming as a mechanism to prevent takeover of the visual cortex. bioRxiv, 2020-07.