Recently, for the first time, I realized that I was dreaming as I was having the dream. This was due to critical thinking - which usually doesn't happen in dreams. We'll look at why lucid dreaming and critical thinking might go hand in hand.
Lucid dreaming is still a contested area of study among scientists. Much of the time, it's been relegated to the "junk science" end of psychology and sleep studies. At most, scientists seem to be willing to admit that sometimes people become aware that they are dreaming while they are still in the dream. One study showed it happens in somewhere between one and two percent of the population.
Considering what happens during dreams, a lot more people should be catching on that they're not awake. This is one of the great mysteries of sleep science. No matter how much practice we get at observing how the real world works, and no matter how many times we see weird things happening in a dream, we never seem to realize, at the moment when our father turns into a giraffe, that this is most likely to happen in a dream world, and that we are therefore dreaming. This is a shame, because most guides to lucid dreaming assure us that once we realize we're in a dream, we can direct the dream the same way we can direct our imagination.
Whether the kind of real, directed, I-can-fly lucid dreams that these guidebooks describe exist or not, there does seem to be some kind of link between imagination, awareness, and critical thinking. One of the first studies on sleep found that two things are missing during dreams: critical thought and imagination. Lack of critical thought is obvious. When we are asleep we accept at face value all kinds of weird stuff. Lack of imagination is less obvious, but another major part of dreaming. Although, when conscious, we can imagine being impossible places or doing impossible things, we almost never are able to use our imaginations in a dream. No one dreams about day-dreaming. Everything that we think about is literally happening. Perhaps once we gain critical thought during dreams, and awareness of our real state, we also gain the ability to mentally direct our minds any way we want in a dream.
Unfortunately for me, when I realized I was dreaming, I just woke up. It wasn't a pleasant dream. I dreamed a vampire was trying to get into my house. (The Nosferatu kind of vampire, not the sexy kind.) This, I accepted, although clearly my critical-thinking skills were sharp, as I wondered how he could go out in the sunlight. It was only when I picked up my phone to dial 911, and noticed the "9" was missing, that it occurred to me that something was off. I searched my mind as to why the "9" (and in fact the entire bottom row of numbers) was missing from my very-familiar phone, realized that I must be dreaming, and promptly woke up.
Damn. I could have turned that vampire sexy. Have you ever realized, logically, that you were dreaming? How did it happen?