Error, humility and grace

I was having a conversation the other night with friends about error, humility and grace. The upshot was this: If we are honest, we will admit that we have been mistaken about things in the past--including matters of theology and doctrine. We can thus infer that we are probably currently mistaken about some things--including matters of theology and doctrine (but, of course, we don't yet realize *what* things we are mistaken about). This ought to make us humble and gracious towards other views. If we are going to err (and we most certainly are going to err), let us err on the side of grace and compassion.