How I Know I'm Not Dreaming (I Think)
I'm not dreaming. Neither are you.
Oddly, the second sentence seems to be self-confirming in a way the first isn't -- if it refers to an actual "you", that is, if anyone other than me actually reads the sentence, then the sentence must necessarily be true (barring paranormal dreamer-to-dreamer communication). But of course this doesn't imply that I have any special knowledge of your waking state. It's merely a trick of language....
How do I know I'm awake? Responders to the previous post, and others I've questioned, tend to offer the following grounds for knowing:
(1.) Sensory experience is more vivid or detailed in waking than in dreaming. The pinch test may be a version of this. Some claim not to feel their feet on the floor or to be pained staring at the sun. Others say the wide panoply of current visual experience would be impossible in sleep. (Jonathan Ichikawa has recently been arguing that it's not even sensory-like experience we have in dreaming but rather only imagery.)
(2.) Sensory experience is more stable and organized in waking than in dreaming. Some people, for example, say that the words on a page (or on a computer screen!) won't stay still during dreaming, or that a clock's time will be strange or blank or keep changing.
(3.) I cannot do some actions that I can ordinarily do when I try to do them while dreaming -- for example, I can't fly.
Now, I'm inclined to dismiss (3). Maybe, if I can fly, I can rightly conclude that I am dreaming, but the reverse doesn't seem to follow. I suspect that it's perfectly normal to have dreams in which one cannot fly, etc., even if one wants to (unless, perhaps, one realizes one is dreaming and so takes command of the dream, as in lucid dreaming).
(1) and (2) are more tempting. In fact, when I started planning this post I thought I might go for a version of (1). But here's my problem: I go to a quiet place and close my eyes. I still feel quite confident I'm awake. But my visual experience is not very distinct or organized -- certainly not so distinct and organized that I couldn't imagine my brain producing just such experience during sleep without the aid of external input. My auditory experience is pretty vague and thin too. I feel my feet on the floor, of course. But could it really come down to such a slender thread? Is that really my only basis for knowing I'm awake? What if I found a way to deprive myself of vivid or organized tactile sensation too (e.g., by floating in water)? Would I then have no basis for knowing whether I'm asleep or awake?
So maybe we should consider:
(4.) There's some direct and intrinsic knowledge we all have when we're awake that we're awake -- knowledge that's somehow immediate, not on the basis of anything sensory or quasi-sensory.
I point out that accepting some version of (4) -- or (1) or (2) -- does not imply that I can always know that I'm dreaming when I am dreaming. In dreams, we are often confused and leap to weird conclusions. This fact no more undermines my coherent, unconfused present knowledge of my wakefulness than the fact that a deluded, confused person might mistakenly think he's a philosophy professor undermines my non-deluded, non-confused knowledge that I'm a philosophy professor. Our opinions are differently grounded.
Now I wonder where in the philosophical or psychological literature we can find someone who develops an idea like (4). No one comes to immediately to mind, but surely there's someone....