All that exists is made of matter, but existence is not made of matter. Instead, Nature is defined by the motion of matter, not matter per se. It is the energy that moves and transforms matter that renders the phenomenal exhibition we call Nature. Without energy, matter would not exist. Indeed, matter is made of energy. Though there are several proofs, atomic bombs most poignantly make that point.
To understand motion is to understand Nature. ~ Leonardo da Vinci
As matter is energy transcribed, to understand Nature requires comprehending the nature of energy. There the search comes to a dead end, as energy is nothing at all.
Energy is just a label that physicists use to explain how matter moves and transitions through phases: gas, liquid, solid, and plasma. Energy is nothing but an idea. Energy cannot be measured directly; instead, only by its effect on matter.
To recap, matter is solely sourced by an abstraction which physicists call energy. Matter exists, but energy does not. As matter is made of energy, the material world must be a mirage. Fantastic as it sounds, there is no getting around what physicists have irrefutably found.
Now that we understand motion, we may understand Nature. Objectively, motion is an illusion, which means that Nature – the exhibition of existence – is merely an appearance in the mind. Everything is subjective: the product of perception.
There is no “objective” world. Instead, there is only a shared subjectivity. How can that be (or not be)? That is the question.