There is a phenomenon called “leaving the stream of the known.” We seek security through the known, even though there is inherently no security, even in scientific knowledge, much less through accumulating experience. So why are we afraid to leave the stream of the known, the darkening shadow of the past? But it goes beyond that, since short of illumination, even those who’ve left the stream of the known revert to it. And given that it occurs within one, why does the mind/brain return to the stream of the known after having left it?