Currency (money) generally is value. Different cultures historically have agreed to connote value by different means. And I think this has always been by mutual admission. It also always depends on what runs or drives the society at that particular point in time. It is undebatable that the world today is driven by technology. And a lot of what we value today is influenced "digitally". So, it only makes sense that money, currency should also take likewise form. And I think that Blockchain presents a very decent solution.