The Middle

Some philosophers have concluded that what we think of as the "real world" could be or is an illusion (an idea known as the skeptical hypothesis about ontology).

The first recorded mention of the idea was by Zhuangzi, and it is also discussed in Hinduism, which makes extensive use of the argument in its writings.[20] It was formally introduced to Western philosophy by Descartes in the 17th century in his Meditations on First Philosophy. Stimulus, usually an auditory one, becomes a part of a dream, eventually then awakening the dreamer.
Postclassical and medieval history

Some Indigenous American tribes and Mexican civilizations believe that dreams are a way of visiting and having contact with their ancestors.[21] Some Native American tribes used vision quests as a rite of passage, fasting and praying until an anticipated guiding dream was received, to be shared with the rest of the tribe upon their return.[22][23]

The Middle Ages brought a harsh interpretation of dreams. They were seen as evil, and the images as temptations from the devil. Many believed that during sleep, the devil could fill the human mind with corrupting and harmful thoughts. Martin Luther, founder of Protestantism, believed dreams were the work of the Devil. However, Catholics such as St. Augustine and St. Jerome claimed that the direction of their life were heavily influenced by their dreams.
In art