"In quantum physics, the Heisenberg uncertainty principle is the statement that locating a particle in a small region of space makes the momentum of the particle uncertain; and conversely, that measuring the momentum of a particle precisely makes the position uncertain."
Basically, what this says is that you only know where something is or in what direction that it's traveling, but you can't know both. This intuitively makes some sense. If I throw a baseball, you can snap a picture of it, but the clearer the picture is, to the point where it appears frozen in mid-air, the less you can tell where it was going. A blurred picture of a ball, however, clearly has some direction, but you often can't actually tell where the ball was at the moment the picture was snapped.
I've had a number of conversations with people lately about how people change over time. This is an especially important consideration when it comes to getting into a long term relationship. You may like someone now, but how do you know they won't change on you over time? Or, how do you know if people can change the things you seem to clash on?
A lot of it has to do with the how much of a person's personality is innate, static.. an unchangeable core drive particular to them that will permeate everything they do and all their interactions with others. This is what I think of, relative to Heisenberg, as someone's "position". You may think I am an easygoing guy, but that's only at this given moment in time. The more detailed you get in your perception of exactly how I am easygoing, in what situations, what my limitations are, etc., the less you can bet on whether or not it will continue in the future. Not only does the future bring with it lots of unpredictable situations--situations that might test the limits of my easygoingness, but the future also has a cumulative effect. The harsh realities of life my harden me and I may become more difficult over time. I think it is likely I will resist this better than most people, but when you start talking about the momentum of the 57 or so years remaining in my life, it's difficult to nearly impossible to determine what my position will be.
You can, however, describe that momentum. I'm a big believer in one's ability to guide future decisions about your own life with a strong hand. I can decide, and I have, that I will always attempt to avoid stressing the small stuff. Whether I will be successful, what I will learn by doing that, what kind of a personality that will result in, etc. is unclear. However, my future actions are a series of individual choices--choices I do have some control over and can construct a framework for decision making that I can use consistently going forward.
So, for example, a couple can agree to strive to communicate well. They can, with some accuracy, describe a momentum of communication. Communicating is a verb. You cannot be communicative unless you are actually in the mode of openly communicating. That's not an innate trait... it's an action. It's something that people decide to do. Where that communication will lead, whether those people will communicate the same positions going forward is impossible to determine, but at least you can, with much better accuracy, tell how you plan to act.
I'm largely unconcerned with people's position when I meet them. I don't really care much about who you are, because, with every passing second, who you are is a thing of the past. You are what you are doing now, and what you are doing now is already over. I want to know what you will choose to do--how you will choose to live.
It sounds overly simplistic, but I think the best relationships, be them romantic, platonic, professional, otherwise, are the result of a decision--a decision to act in a way that promotes a great relationship. It's not about whether you are inherently respectful, engaging, or interested, it's whether you choose to respect, engage, and take interest. I really believe that, so long as they're attracted to each other, just about any two people should be able to get together and half an absolutely fantastic, exhilarating life together--and that falling short on that is largely a product of lack of commitment on one more both sides to do the actions necessary to promote a good relationship. Sound too easy? It's easier than you think, if you make it.