Pragmatic optimism is the best. You don't delude yourself that everything is okay when it's clearly not, but you know that you can handle most challenges thrown at you and you use the best methods suitable for handling any problems. You are only negative if it's worth being negative about. And this is about the things that are changeable and you are negative so you would know what you have to change or improve. You give benefit of the doubt to people as much as is reasonable.