That's more or less the meaning. If, some years ago, a couple of men did not have the imagination to see that computers would be wanted by most people - Apple Computer would never have been formed. If a country wants clean water, they first have to imagine how this can be accompolished. After working on the problem of getting clean water to all of the people for some time, the task of getting clean water becomes more and more possible. Another way of saying this is - first there has to be the vision, then the work, and, finally, the end result.