I am not saying that this is what I believe, just speculating:

What if life is all a dream? What if what we perceive as being waking reality is just a repeated dream, with laws of physics and such just due to our expectations - or more specifically if it is a big shared dream the laws of physics would be due to shared expectations, and thus very hard or almost impossible to break because then someone would need to reach a level of lucidity (enlightenment) with awareness and control strong enough to counteract shared expectations.

The other day I had a memory which I realized I had no way to tell wether it was a waking memory or a dream memory, and the only way to tell was to call my husband who had been there in the scene in my memory, and verify whether he also remembered it. He did, and thus I decided that it was a waking memory. However, it occurred to me that if at the time I called my husband to verify the memory I was also dreaming, then my "proof" would count for nothing.

What if what we call waking reality are dreams during which we fail to recognize that we are dreaming, even in hindsight. What if those are the times when reality checks fail? Reality checks can really only prove that something is a dream, but can they prove that the rest is not a dream?

Is there any way to prove that our lives are not all a dream?