Descartes and Dreams

Descartes' philosophy questioned almost everything. He used the dream as a means to question the world around him.
Descartes and Dreams
Gema Sánchez Cuevas

Written and verified by the psychologist Gema Sánchez Cuevas.

Last update: 12 March, 2023

French philosopher René Descartes is known for his contributions to philosophy, mathematics, and science. In his philosophical reflections, he pondered on dreams. In this article, we’ll examine his ideas on the subject. We’ll also include his renowned Cartesian doubt and how it was related to the phenomenon of dreams, as well as his existentialist character.

The everyday experience of dreaming has long been the subject of philosophical discussion. That’s because it opens up the extremely important question of what stops us from believing that what we call reality isn’t a dream. You might find this particular idea unimaginable, but it’s long been an interesting concept for philosophy. Let’s see what it has to say on the subject.

Sleeping woman in bed

Descartes’ theory of the dream

Descartes’ dream hypothesis first appeared in the mid-17th century in his work, Metaphysical Meditations. This book was first published in 1641. It explored issues such as existence, truth, knowledge, and reality. Descartes wanted to find facts that allowed him to build precise and infallible scientific knowledge. This was because the science of his time was full of errors.

Descartes maintained that, when we dream, we represent both real and irrational things to ourselves. This means we’re unable to differentiate sleep from wakefulness. Therefore, if science takes its meaning from the world around us and this is called into question, what are we left with?

Descartes wondered about the content of dreams because, no matter how unlikely they are, they have their origins in reality. Therefore, they have to have a resemblance to real things.

The things we see in dreams are like painted images, which we could only have imagined from the likeness of real things.

However, this didn’t help the philosopher to establish a difference between sleep and wakefulness. This is where his famous hyperbolic or Cartesian doubt comes in. Indeed, from that moment on, he started to doubt everything in the world, such as mathematical truths.

He did try to find at least one clear and evident truth. He found it in thought. His famous saying “I think, therefore I am” is based on the idea that his ability to think meant he existed and there was no chance of that being called into doubt.

Dreams and existence

Although the dream hypothesis is used as a resource to establish hyperbolic doubt and thereby find certain and secure knowledge, it can have another interpretation. This other meaning considers the dream as a means to raise existential or vital concerns.

The problem of existence raises the impossibility of knowing whether or not we live in a dream. If this is so, our reality and the world around us would be an everlasting dream. If we woke up from it, we’d cease to exist and would lose everything we think we know. It’s a distressing thought.

“No, you only exist as a fictional entity; you are not, poor Augustus, more than a product of my fantasy and those of my readers who read the story that I have written about your feigned adventures and misadventures…”

-Miguel de Unamuno-

With Descartes’s dream hypothesis, not only scientific knowledge starts to wobble, but also existence itself. On this basis, if we woke up, nothing would remain.

Descartes and the moral problem of the dream

Descartes’ deep philosophical reflections on dreams and knowledge allowed him to reach the most certain and sure truth that he could ever arrive at: “I think, therefore I am”.

There was also a moral component to Descartes’ work. In fact, his reflections sought to dominate the life of the human being as well as nature. This meant finding an accurate and secure truth. He suggested that reason had the impulse or desire to reach it. Therefore, our morality would depend on the degree of certainty that we have of things. In effect, the more true knowledge we have of the world, the greater the control and management we can exercise over our lives.

Descartes believed that if we master our life through true knowledge, we can also master nature. We use true knowledge to advance scientific knowledge and science takes the objects of the world that surround us to expand wisdom. Consequently, this gives us a better knowledge of the world and greater management and control over it.

“The word ‘philosophy’ means the study of wisdom and by ‘wisdom’ is meant not only prudence in our everyday affairs but also perfect knowledge of all things that mankind is capable of knowing, both for the conduct of life and for the preservation of health and the discovery of all manner of skills.” 

-Descartes-

Sleeping woman dreaming of the sea

The dream as a critical attitude

As we’ve explored in this article, the dream played a crucial role in Descartes’ philosophy as a tool for exploring the nature of reality and truth. By reflecting on our dreams and the nature of reality during sleep, Descartes suggested we question the truth provided by our senses in the waking world.

Therefore, for Descartes, the dream became a tool for fostering a critical attitude toward our beliefs and perceptions. Through his study of the dream, he was able to seek more solid and secure knowledge based on reason and clear and distinct evidence.

Ultimately, the role of the dream in Descartes’ philosophy illustrated the importance of critical reflection. It also highlighted the role of methodical doubt. Indeed, his philosophy served to find true knowledge and better understand the nature of the world around us.


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