According to Harvard psychologist Deirdre Barrett, at least part of the reason we sleep is to process the thoughts and problems that trouble us during our waking hours. Barrett’s theory posits that the illogical aspects of dreams and the vivid visual images we experience during our dreams provide a way to process the kind of out-of-the-box thinking that isn’t possible during our usual reality.
Whatever the reason for your dreams, the likely answer is that your dreams have evolved to fulfill multiple functions. Critical thinking may be one reason, information processing might be another. Even with the tremendous scientific strides we’ve made in the 20th and 21st centuries, there’s still much about sleep and dreams we really don’t know. Who knows, maybe dreams really are a veiled window into our baser urges and impulses, like Freud suggested.