Do shared dreams exist?
There are testemonies about shared dreams, but I havn’t seen that they have been proven under controlled circumstances (that is, in research). If that would be the case, it would represent a watershed as to what it means to be human and how the mind relates to the brain.
It seems like the people telling of shared dreams have had close relationship with eachother in real life. Moreover, I think their experinces from a shared dream would not be exacly the same, but close enough as to make a shared dream a possibility.
Personally, I think shared dreams can occur. This is because I think the mind, although coupled to the material processes of the brain, represent some other aspect of nature than what we normally perceive as a material world, and therefore not limited by the same rules that govern material interaction, for instance that minds don’t have to be parts of the same “physical” system to interact. There are sides to modern physics that are quite strange, especially the quantum phenomena, that in the future might lead to new interpretations of the nature of reality (well, to some degree they already have). But for the notion of shared dreams to be widely accepted, there has to come some solid research that makes it very propable, and even then there would be room for interpreations. Maybe a 100 years from now they will be seen as evident, but then maybe not. Maybe the extraordinary phenomena of shared dreams will forever evade the consistency in reseach required for them to be accepted among the believers of science.
The basline is: Seeing is believing. For some, accounts from someone they trust (or don’t see any reason to distrust) would be enough. For others, repeated affirmations from independent and rigorous research would count as seeing, but then, for yet others, not even this would do, as the results would treaten their established (i.e. materalistic) worldview.