Adams, who worked on Google+ before moving on to Facebook, gives his general thoughts about the relationship model G+ is going for with Circles. His last thought is really interesting:

Finally, it’s worth noting a trend that will make the task of representing relationships online even harder. Many fields of science are starting to discover that most of our behavior is driven by our non-conscious brain, not by our conscious brain. This refutes much of our understanding of how the world works. When we meet people, for the first time, or for the ten thousandth time, there are far too many signals for the conscious brain to take in, analyze, and compute what to do. So our non-conscious brain does the analysis for us, and delivers a feeling, which determines how we react and how we behave. It’s our non-conscious brain that will be deciding which social network succeeds and which one fails. It’s going to take most, if not all, of our lifetime to figure out what is happening in the non-conscious brain. This is just the beginning.

I’d go even further. If it’s true that the non-conscious brain is responsible for much of our social behavior, that may mean that no online service will ever truly be able to replicate real-life interaction and relationships (which Google says they’re trying to do with Google+). Or at least not until we have computers that actually tap into our brains.

Subconscious actions don’t really translate online. At least, not in the same way that they do in the real world. Too much of what we do on a computer is explicit. Missing are the thousands of subtle things you can perceive when hanging out with someone in person. 

The more I think about it, the more I’m just not sure all these social services should bother trying to re-create real-world social dynamics on the web. It sounds like the right thing to do, but maybe it’s just a totally different sphere with totally different rules.