"The 'world-as-seen' is constructed by the brain in the same sense as any virtual reality; in other words, virtual space is the only reality. In fact, 'virtual space' exists and has existed within what would commonly be considered the 'actual space' that we inhabit - that is, Euclidean space, topological space, Cartesian space and Newtonian space."
Faith and Virtuality. Christian Groothuizen. 2001. p.138