Fear and Curiosity

It's open to question all the different attitudes one can approach life with or the reactions one can have to it. What is the difference between living in fear of uncertainty about the future and living assured things will turn out predictably and maybe even favorably? Is there a kind of flow state possible in the everyday lives of some people, or a brain chemical that pumps out confidence, like a natural prozac that prevents fear from taking hold? Or can that kind of phenomenology be willed into existence, catalyzed by action or by a combination of positive action and positive attitude? It crossed my mind that the constant desire to learn more, intellectual or technical curiosity is one such antidote for fear, as it keeps the mind occupied, focused, the way a predator's attention while stalking its prey blocks out ordinary considerations of possible risk exposure. A mind constantly learning questions assumptions and beliefs. Being habituated to experiencing the fallibility of what one knows produces comfort through repetition, like all habits do, but what combination of directedness and sense of purpose infuses this habit to be more satisfying than lazier alternatives? And how is it that one's own tearing down of assumptions reveals underneath anything satisfying rather than sheer terror?