We don't know what we don't know, and that includes the future. Ironically, it also includes the past because events that have transpired, and their meaning changes with our vantage point. But when we look forward from the present and apply what appear to be sound extrapolations, our predictions founder. Vision rationalizes the irrational. And vision is not a compilation of wishes, or a sketchy set of predictions.
Vision is an experience of reality through the medium of sight, therefore it is very tangible.
Vision allows us to define the something that we don't know and thereby take the first step towards knowing it. You can never travel towards a vision. Once you find and inhabit a vision, you bring it whole and intact to the present. You bring it from there to here. The vision begins as an unknown.