Dream argument

Postulation about the act of dreaming

The dream argument is the postulation that the act of dreaming provides preliminary evidence that the senses we trust to distinguish reality from illusion should not be fully trusted, and therefore, any state that is dependent on our senses should at the very least be carefully examined and rigorously tested to determine whether it is in fact reality.

Dreaming provides a springboard for those who question whether our own reality may be an illusion. The ability of the mind to be tricked into believing a mentally generated world is the "real world" means at least one variety of simulated reality is a common, even nightly event. Those who argue that the world is not simulated must concede that the mind—at least the sleeping mind—is not itself an entirely reliable mechanism for attempting to differentiate reality from illusion. Whatever I have accepted until now as most true has come to me through my senses. But occasionally I have found that they have deceived me, and it is unwise to trust completely those who have deceived us even once.

In the past, philosophers John Locke and Thomas Hobbes have separately attempted to refute Descartes's account of the dream argument. Locke claimed that you cannot experience pain in dreams. Various scientific studies conducted within the last few decades provided evidence against Locke's claim by concluding that pain in dreams can occur, but on very rare occasions. Philosopher Ben Springett has said that Locke might respond to this by stating that the agonizing pain of stepping into a fire is non comparable to stepping into a fire in a dream. Hobbes claimed that dreams are susceptible to absurdity while the waking life is not. Many contemporary philosophers have attempted to refute dream skepticism in detail (see, e. g., Stone (1984)). Ernest Sosa (2007) devoted a chapter of a monograph to the topic, in which he presented a new theory of dreaming and argued that his theory raises a new argument for skepticism, which he attempted to refute. In A Virtue Epistemology: Apt Belief and Reflective Knowledge, he states: "in dreaming we do not really believe; we only make believe." Jonathan Ichikawa (2008) and Nathan Ballantyne & Ian Evans (2010) have offered critiques of Sosa's proposed solution. Ichikawa argued that as we cannot tell whether our beliefs in waking life are truly beliefs and not imaginings, like in a dream, we are still not able to tell whether we are awake or dreaming. Norman Malcolm in his monograph "Dreaming" (published in 1959) elaborated on Wittgenstein's question as to whether it really mattered if people who tell dreams "really had these images while they slept, or whether it merely seems so to them on waking". He argues that the sentence "I am asleep" is a senseless form of words; that dreams cannot exist independently of the waking impression; and that skepticism based on dreaming "comes from confusing the historical and dream telling senses [of] the past tense" (page 120). In the chapter: "Do I Know I Am Awake ?" he argues that we do not have to say: "I know that I am awake" simply because it would be absurd to deny that one is awake. The dream hypothesis is also used to develop other philosophical concepts, such as Valberg's personal horizon: what this world would be internal to if this were all a dream.