Second Reality is like a mouse in a maze...
First reality is totally FREE..
Things are easily measured in a maze..
Which brings to mind.. can humans measure anything accurately..
I know a bit poetic but just being human may be a second reality..
To wit; a human that dies may enter first reality..
You know there may be "qualities" of second reality's..
i.e. some better than others.. higher digs as mazes..
I'll avoid the "second reality" term as it has a specific meaning in Voegelin/Musil philosophy, roughly an imaginary world a person conjures in lieu of the actual world.
But indeed, the reality we mortals experience with our severely limited 4D minds and vision (3 space and 1 time) is but only one reality. When we graduate from this one (or phase change following Wesson's theory) - we will experience a different reality.
For us Christians, it will be heaven. And according to Revelation there will be a new heaven after that. And, of course, some of us Christians expect a stay in purgatory first. Some expect a long sleep first.
And also according to Scripture, there will be other, unpleasant, destinations...