I didn't write that title thinking about visualization, but it came to mind as I thought about how to open the blog entry.
It's important to have a vision of what you're trying to accomplish. With a vision, you can make a plan, and with a plan, you can move most efficiently towards achieving what you want to achieve. Without a vision of what you want to accomplish, you're waiting at the whim of fate. This may work out well, but it's not something you have a lot of control over.
The idea of visualization is related to the need for a vision. Athletes often improve their performance through visualization exercises--visualizing their performance in the optimal form helps them bring that optimal character to the real performance. This can be seen as being much the same basic process by which a vision of the future can help all of us: the vision is a model on which we can work, which allows us to guide and refine our efforts to their best effect in our search for our goal.
Swiss philosopher Ferdinand Gonseth wrote a fable that my former dissertation chair, Prof. Jean-Pierre Protzen, of U.C. Berkeley, wrote an article about. In that fable, whose purpose is to question decision-making processes, one character asks another "would you let the dice decide"? This seems like the crucial question with respect to the desire for a vision: are you going strive for something that you want, or are you going to allow yourself to accept whatever the dice serve up? As Protzen points out, we think (we hope) that we can do better than simply letting the dice decide.
Having a vision for the future that you wish to achieve is not necessarily a loss of freedom: having a vision for the future that you want does not mean that you can't change your vision whenever you wish, it just means that you will more effectively pursue whatever vision you have chosen to pursue.