Like all good tales, this is a story about temptation. It all begins with Kant. In the first Critique, Kant posed the fateful question: how is a priori synthetic knowledge possible? Among the items of undoubted knowledge to be accounted for: that the world as revealed by experience shall be in a Euclidean space; that it shall be governed by deterministic laws; that all substance is permanent, being neither created nor destroyed. The detailed argumentation brought forward in support of these claims is famously obscure, but the general outlines of the position are easy to sketch. We can know a priori that the world of experience will conform to these principles, not because they are conditions on things as they are in themselves, but rather because they are conditions on how things must be presented to us and conceived by us and judged by us in order to constitute experience. Items of experience must be given to us in perception, and so are subject to the forms of perceptive intuition (space and time). Further, in order to judge that our perceptions are of objective things, the appearances of things must conform to certain rules. In short, a priori synthetic knowledge is possible because it is not knowledge of how things are, but knowledge of how the world as revealed by experience must be, in order to be a world revealed by experience. The progress of science was not kind to Kant.
The idea that what we experience as physical-material reality is what's actually there is the flat Earth idea of our time. That is, the idea that physical-material reality is what's actually there where we experience it to be is an idea that, based upon appearances, seems to be true, in the same way that while standing in the middle of Illinois the Earth appears to be flat, but from a broader perspective is seen to be but an illusion of limited perspective. That broader perspective is afforded by the limitations of experience revealed by quantum physics in the form of the phenomena of wave-particle duality, quantum uncertainty, and quantum entanglement, which limitations, in revealing the nature of experience to be Experiencer dependent, provide insight into the way in which experience is created as the product of a relation of Consciousness, i.e., What Is Actually There, to Itself. However, the same limitations of experience revealed by these phenomena serve to hide from view what these phenomena reveal about the nature of experiential reality, including how experiential reality is created, when considered within a materialistic framework, i.e., within a framework wherein material reality is conceived of as being what's actually there. Thus, although it may seem that we live in a world of material cause and effect, we actually live in a world of Existential cause and experiential effect. That is, we live in a world where the cause is always some relation of Consciousness-Existence to Itself, and the effect is always the experience that is created and apprehended by the Individual Consciousness involved in that relation.
The idea that what we experience as physical-material reality is what's actually there is the flat Earth idea of our time. That is, the idea that physical-material reality is what's actually there where we experience it to be is an idea that, based upon appearances, seems to be true, in the same way that while standing in the middle of Illinois the Earth appears to be flat, but from a broader perspective is seen to be but an illusion of limited perspective. That broader perspective is afforded by the limitations of experience revealed by quantum physics in the form of the phenomena of wave-particle duality, quantum uncertainty, and quantum entanglement, which limitations, in revealing the nature of experience to be Experiencer dependent, provide insight into the way in which experience is created as the product of a relation of Consciousness, i.e., What Is Actually There, to Itself. However, the same limitations of experience revealed by these phenomena serve to hide from view what these phenomena reveal about the nature of experiential reality, including how experiential reality is created, when considered within a materialistic framework, i.e., within a framework wherein material reality is conceived of as being what's actually there. Thus, although it may seem that we live in a world of material cause and effect, we actually live in a world of Existential cause and experiential effect. That is, we live in a world where the cause is always some relation of Consciousness-Existence to Itself, and the effect is always the experience that is created and apprehended by the Individual Consciousness involved in that relation.