Common Elements in Dreams

I was looking over a list of "Reality Checks" the other day. You know the ones that help you kickstart a lucid dream - when it occured to me...most people have these common elements in dreams. Kind of like a whole different set of physics for dreams. For example when you look at your hand you will most likely have more than five fingers, or turn on a lightswitch it will work only about half of the time. To me this suggests that on some fundamental level, people are wired basically the same way - to be able to have these same occurences.

But what i want to know, is does anybody out there know why? Why is it that so many people report having the same experience with extra digits? What is it about the brain that so many people report they can't turn on a lightswitch?

A big part of the reason for this is that we all share stories. If one person says they have problems turning lights on, then anyone who hears about it is more likely to believe that they too will have the same problems, and then they do. Dreams are based in our beliefs and so as long as we all share similar beliefs, we will all notice similar phenomena in our dreams.

Yeah good point, but even without sharing stories people have similar dreamsigns! Physics in dreams seems to be more unstable. People report these dreamsigns indepently from eachother.. so I'm also wondering how this is possible

I've honestly never experienced either of those. o_o Especially not with my fingers! Trouble with lights, possibly, but in the dream it seems to take the form of power outages...hm.

I myself have the common dream sign of trying to dial a phone number and it's practically impossible, or reading something and then it changes. I've heard these are extremely common signs of being in a dream, too (except I'm always so flustered with the phone that I never go lucid). I've heard that one can never read the same thing in a dream twice, and for me this has been true.

I think it's the same principle at work regarding extra digits and light troubles and such. Something doesn't work in the way that it's supposed to, or keeps changing. I think this is just the fundamental nature of dreams being so transitory. They're not stable and unchanging like real life--they're very fluid and mutable. Phone numbers don't stay the same, the words in books change, even body parts morph into something else. (I've had ALL KINDS of dreams where my physical appearance is significantly altered.)

I'm betting that in other cultures where they don't use lightswitches or telephones, they too have similar dream sign experiences with things that refuse to be the same way twice. That's just the way dreams are, because they're constantly changing.

Thank you all very much for your replies.

What Xaqaria was saying sounds feasible if not for the fact that I had some of these experiences regularly before i ever read about a lot of other people having them too.

I mean I understand that not everyone is going to have the same experience with the multiple fingers, or the lightswitches...or being able to read. I picture it like most people being right handed, and only a handful are lefties. I don't know, maybe i'll take a poll later or something.

Most people i've talked to (but not all) seem to have the similar experiences of changability in their dreams. Thanks to tehuti88 for reminding me of the reading thing, which seems to be another common element. I can't read worth squat either.