All we have is what is experienced. If something is not experienced then it does not exist from our perspective. Sure, it can be theorised that there are many things we do not experience, but that is nothing more than a passing thought not referring to anything at all, in other words, pure fiction. What is actually experienced is apparently unstable, impermanent, since there is nothing within the six sensory areas that one can find to be constantly present. Nevertheless, because mind has the ability to imagine all sorts of things, we conceptualise time, and that things continue to exist over time, so we attribute them constancy, even when there is no constancy experienced in reality. And if we look closer, clearly what is past is already gone, it exists no more, and what is in the future does not exist yet, so all we are left with is what is present, but the present moment is actually nothing we could pinpoint, it too is merely an imagined period of time, a fictional entity. So where is any permanent entity? Where is any impermanent entity?