Dr. Rudolfo Llinas, who has made a study of dreams says, "If you are asleep, it is called dreaming. If you happen to be awake, and it's very strong, it's called daydreaming. If you are aware of what is happening outside at the same time, it is called thinking."
IOW, we're in a constant dream state. We have to be aware, however, of the difference between being awake versus being asleep, or the difference between dreaming and thinking.