> I think a truly "smart person" is someone who is always staying open to the possibility of people changing radically, however unlikely that may seem.

But a truly "person who is currently acting smart" may realise that they simply do not have the time to continue treating this "person who is currently acting stupid" as if they're simply acting that way, and may make a temporary value judgement about that person fully in the knowledge that it's an over-simplification and useful only in the present situation. Doing so may also be a smart thing to do, as it allows said person to actually get something done.