The Nature of Reality II

1. It's hard to imagine what the world would look like if we weren't there to experience it, simply because the act of imagining it involves our presence.  Would there necessarily be any world if we were not there to experience it?  It would be simply a matter of assertion, about which there could be no direct evidence.
2. Since we cannot demonstrate the existence  of the world when we are not experiencing it, we have to doubt it.
3. We cannot even demonstrate the existence of the world when we are apparently experiencing it.  I have already said in the previous post that we perceive only images.  Even if we were to concede the existence of eyes and a brain, what we are perceiving must be created by us somehow, there's no way of establishing that those images represent some reality external to us.

There is a big mental problem here.  For someone like me who has been interested in the scientific view of the universe for a lifetime, it's a very big change to start questioning the very existence of that universe.  It's an exciting feeling but how can I actually start to believe in what logical enquiry is telling me? For eight decades I have been believing stuff that now, upon careful enquiry, starts to look like mere assumptions, mental constructions - for there can be no doubt that that is what our "knowledge" of the universe amounts to.