Fear is also utilized when our common sense or logic dictates that a continuance of something may well turn deadly. So in some sense fear is a good alarm for safety. But many times fear is just being afraid and that is not as healthy when combined with our other natural instincts of care and wonder. Being afraid to expand or learn is always difficult to defend. We are better off learning and growing than to be afraid of the consequences of that learning and growing. Ignoring harms or threats to our existence is also not good. Ignorance is not something our human species should ever settle for. We are capable of much much more than choosing not to know. It is beneath our dignity really.
As to courage, we must balance our need to know and act with our need to be safe. It really is a critical balance that must be weighed carefully. I can be cavalier at times with my hero ego and try to do difficult acts to save someone or myself with little thought. I have a difficult time with the hero ego since I suffer from the delusion that I can be invincible at times. lol. However, my courage is strong and it is a direct result of my wanting to know, or my curiosity. We humans must live up to our great potential and apply our courage where needed. Courage to face our demons or our fears often leads us to conquering them and then moving on to the next great challenge. It is who we are as a species and we had all better begin to comprehend that.