While I enjoyed the essay, I have my quarrels with it.
First of all the over-generalization: why would all successful people do the same thing? Why would there be only one road to succees? People are different.
Second: the lack of definitions. Is "leave everyone better than you found them" a goal? It would appear so. What about "leave no one worse-or-equal than you found them"? Looks like a constraint. And yet they are the same rule.
Lastly: the lack of backup. Except for some interpreted anecdotes, there's not much evidence there.
Points for creativity and engaging style. But could do more on evidence and clarity.
To your second point: For me, the major difference between goals and constraints would be that I can clearly achieve a good goal, but a constraint is something that will never be fulfilled. A good goal is to run and complete a 10k marathon, it's easy to tell when you're done, or if you failed, potentially even measuring how far off you were. But a constraint would accompany you until you choose to disregard it. You can respect a constraint, but you can never complete it, only in the context of a finite project.
To me, a lot of this post sounds like goals vs habits, caring more about what you do today than what you may achieve sometime in the future, only that the habits are constraints here, so not doing something. In short, "leave everyone better than you found them" is something you can adhere to constantly (like a habit), but for it to be a good goal you would have to know when you're done finding people I guess.
Ultimately, what I read from this post is that constraints are used to provide identity, to help you guide yourself everyday. And maybe that's what you need more than goals if a lack of identity (in your work) is what's troubling you.
This was a neat way to put it. Goals have always bothered me because they are an excuse to stop working – either because they are fulfilled, or because it becomes clear they will not be fulfilled. Constraints don't have the same problem.
Goals have always been more like milestones to me and also something that you can change. I see goals and constraints both as different kind of tools to be used. If you decide to change direction, both of them can change.
Put this way (P and GP) this makes a lot more sense. Thank you, glad you chose to share!