[Nogrod]

I'm not sure if Gandalf's reactions to the Ring are best or most fruitfully defined in terms of humility vs. pride...

If you wish to talk with the pride - humility vocabulary, one might say there is the somewhat prideful self-assessment ("I could do wonders with that thing unlike you because I'm special.") and the somewhat humble acceptance ("But in the end I couldn't resist the power of that Ring which is more powerful than I am.").

He senses the desire in him to wield it and make good with it - but at the same time he fears / knows that it would turn him into a monster equal to Sauron. So he knows he has power and could make a difference with the Ring in the war (unlike Gollum or Bilbo in a sense that neither of them could have become a "ruler of the world" with it) but also realises his powers might / would not stand against the power of the Ring.

So I would think of that rather in terms of clear thinking, being careful, thoughtful and acknowledging one's place in the world rightly. So self-knowledge and understanding, like Aristotle thought of the virtuous person - where both (wrong) pride and (self-worth -ignoring) humility were vices?