Topics Mind

Question Are dreams experiences that occur during sleep? Or are they made-up memories that only occur upon waking? How could one tell either way?

Accepted:
January 26, 2011

Comments

Good question, one that has been debated by philosophers (perhaps even psychologists?), and one that is answered nicely in Owen Flanagan's Dreaming Souls. You can get a glimpse of the problem on p. 19 found here but he gives the full answer later in the book (e.g., pp. 174-5). Basically, this question offers a nice case where we have to go beyond the evidence offered by our first-person experiences. We can't be sure, upon waking up, whether we had a dream a while ago during sleep or whether our minds are very quickly making up false memories that we experience as dreams. (We also can't be sure from our experiences how long our dreams last--Kant and others have thought they occur 'in a flash'. And we can't be sure whether our reports of our dreams accurately convey what we actually dreamed, assuming the dream experiences occurred during sleep.)

If one assumes that our experiences are the only evidence relevant to answering such questions, then one may not be able to answer them. But here we should "go abductive." We should consider which is the best theory in terms of all the relevant evidence--the theory that is most consistent with all the evidence, explains more of it, predicts new discoveries, etc. Here are some reasons to think that the best theory in this case is the one that says we have dream experiences during sleep (T1) rather than constructing dreams upon awakening (T2):

There is a strong correlation between REM (rapid eye movement) during sleep and dream reports: when you wake someone up during REM they often report dreaming and when you wake them up when not in REM, they typically do not report dreaming. T1 predicts that there will be such differences, while T2 has a harder time explaining it (note: you can make T2 fit the evidence but it gets more ad hoc).
Length of time in REM sleep correlates roughly with reported experience of length of dream. Again, evidence for T1 over T2.
The brain changes in regular ways during times that correlate with both REM and reports of dreams upon being awoken. And some of these changes suggest experiences consistent with the contents of dreams (e.g., visual cortex is active and we report visual experiences in dreams, etc.).

And so on. I hope this helps. One lesson, I think, is that the best way to approach some philosophical questions, including (especially?) ones about our minds, is to gather evidence from every source we can and come up with the explanation that best fits that evidence. Of course, it's a philosophical question which evidence is relevant and what counts as best fit!

Question Are dreams experiences that occur during sleep? Or are they made-up memories that only occur upon waking? How could one tell either way? Accepted:January 26, 2011

Question Are dreams experiences that occur during sleep? Or are they made-up memories that only occur upon waking? How could one tell either way?

Accepted:
January 26, 2011