While some 4 p.m. fantasies do come true, a broken clock is also correct twice a day. The age-old notion about the peculiar quality of 4 o'clock dreams, which dates back to Pythagoras, is based on a lot of misunderstandings, a little of sophistry, and some extremely bad math. The first thing you should know is that most dreams occur during sleep. There are several different stages of sleep, and each stage has its own characteristic behaviors. In fact, other than waking up and going back to sleep, humans can only enter another state of consciousness when we sleep. Most dreams occur in the last phase of sleep called REM (Rapid Eye Movement). During this phase, our eyes move rapidly under the control of our brain. We experience sensations such as visions and emotions during these dreams. It is believed that REM dreams help us process information before we wake up. People who suffer from insomnia may have problems entering or staying in REM sleep, which may cause them to feel tired and groggy upon awakening. It is well known that many great ideas are born while asleep. This may be because the mind is free of conscious thought, so it can explore possibilities without restriction. According to research done at Stanford University, people who use their phones shortly before sleeping will often have more vivid dreams. Since phone usage is highest between 4 and 8 o'clock in the morning, this confirms that early morning dreams are real.