“In brief, insight is wisdom which enables one to see that mental states and matter are impermanent or transitory, unsatisfactory or suffering, and impersonal or non-self. What we regard as ‘self’ or ‘ego’ or ‘soul’ are miscomprehensions arising from a lack of knowledge of absolute truth. In reality, ‘self’ is but a very rapid continuity of birth and decay of mental states and matter…” — Achaan Naeb, Vipassana meditation master
The point here is not to denigrate human experience or to fall into a state of existential despair. Quite the contrary, our best shot at inner happiness is to recognize reality for what it is: changeable, unpredictable, and unreliable. “This world is not my home,” to put it in Christian terminology, it is passing away and not a sure source of joy. In all religions and spiritualities that I have studied and can recall, the point is to let go of what we think we need. This is the lifelong process of becoming wise. Think of those wise old men and women. They are wise because they are content with things as they are, effortlessly riding the waves of change.