That's an interesting question. The cynic argues that everyone is on a PR mission and that our true self is when we are in a moment of weakness. The idealist argues that those moments are rare and far in between, and shouldn't define us. But at the heart of the debate is the question of whether there is a "true self" at all. Maybe people do just what people do.

I suspect we try to characterize people because we're attempting to build a Bayesian Model that can help us predict someone's next move. And all that is going to depend on our 'prior' and 'base rate'. In this perspective, there is no "true self" that will be observed by everyone on the planet.