This is the same as a basic comparison in computer language. Is what you are experiencing right now (x) equal to the real world (y)?
return(x == y);
The obvious issue here is that both of these terms need to be defined. X can be defined in qualitative terms, such as the environment and inhabiting objects that can be perceived. However, there is no way to define Y because it can only be defined in relation to X. So a more appropriate statement would be as follows:
y = x;
What this effectively means is that because X is what we are experiencing, Y is the real world, which sounds backward but isn't. If you can only experience things within a certain range, it's pointless to debate what lies outside of that range, and in fact, based on all of our definitions of reality, anything outside of that range would not be reality. A simpler statement would be that illusions are created in the image and likeness of a reality, but if no reality exists, no illusion exists, so one world cannot be proven to be "more real" than another.