It is axiomatic of a system of exploration.
It assumes that we as modeling entities exist, with our models of ourselves and our reality at some scale of resolution.
It assumes that we exist as some sort of subset of some larger matrix (which we normally term reality).
It is supported by a great deal of evidence, but the very notion of evidence is predicated on some sort of set of axioms or principles.
In our case, it seems that this set of axioms has been selected and embodied in us by the repeated, recursive process of the differential survival of variants on themes at different levels of biology and culture and understanding over vast times.
When one starts to seriously explore the systemic spaces of possible systems, and to seriously look at the systems embodied in the many levels of life on this planet, and what seems to very probably be the evolution of understanding present (models of models of models … of complex adaptive systems upon systems upon systems …..); the picture has a beauty and a fractal vastness and eternal uncertainty that holds the potential for continued interesting existence for the balance of eternity, should one manage to mitigate all the many levels of risk present.