All sorts of philosophical systems are built on a foundation. In some cases more than others, a system appears to be founded more or less on an absolute foundation. Often times these foundations are not explicitly expressed, and in the case of philosophy in the contemporary era, they are often outright denied. However, if one looks deeply into any philosophy, I believe that they will find, at root, a foundation off of which that philosophy springs. Some are more evident, and some are more complex, but quite simply, all philosophical foundations assume some sort of foundation, which points to the existence of an absolute or fixed truth. This can take the form of the \"principle of verification,\" which is empiricism, logic, \"will to power,\" and even, in Heidegger\'s terms, \"rootedness\" or \"autochthony,\" a being that just be or is.
It is this root of \"isness\" or being itself out of which all things derive. It reminds me specifically, of the pre-Socratic philosopher, Anaxagoras