We do not know why we appear in this world. We say everything in this world is changing. This world keeps changing. So we say this is the impermanent world. So form is emptiness, emptiness is form.
Mountain is water, water is mountain.
At this point, receiving inka is losing inka. We do not receive inka and do not lose inka. At this point, we say there is no form and no emptiness. No mountain, no water. We call this emptiness world.