Without perception, there is in effect no reality. Nothing has existence unless you, I, or some living creature perceives it, and how it is perceived further influences that reality. Even time itself is not exempted from biocentrism. Our sense of the forward motion of time is really the result of an infinite number of decisions that only seem to be a smooth continuous path. At each moment we are at the edge of a paradox known as The Arrow, first described 2,500 years ago by the philosopher Zeno of Elea. Starting logically with the premise that nothing can be in two places at once, he reasoned that an arrow is only in one place during any given instance of its flight. But if it is in only one place, it must be at rest. The arrow must then be at rest at every moment of its flight. Logically, motion is impossible. But is motion impossible? Or rather, is this analogy proof that the forward motion of time is not a feature of the external world but a projection of something within us? Time is not an absolute reality but an aspect of our consciousness.
This paradox lies at the heart of one of the great revolutions of 20th-century physics, a revolution that has yet to take hold of our understanding of the world and of the decisive role that consciousness plays in determining the nature of reality. The uncertainty principle in quantum physics is more profound than its name suggests. It means that we make choices at every moment in what we can determine about the world. We cannot know with complete accuracy a quantum particle’s motion and its position at the same time—we have to choose one or the other. Thus the consciousness of the observer is decisive in determining what a particle does at any given moment.
Einstein was frustrated by the threat of quantum uncertainty to the hypothesis he called spacetime, and spacetime turns out to be incompatible with the world discovered by quantum physics. When Einstein showed that there is no universal now, it followed that observers could slice up reality into past, present, and, future, in different ways, all with equal reality. But what, exactly, is being sliced up?