I think greed will be our biggest struggle. We will probly always struggle with it. and it seems to be the root of most our problems. Humanity seems to overcome most everything it faces, that is the great thing about us. We can learn to adapt, understand and invent. But at the same time we are the biggest thing holding us back. But to awnser the question, Yes, I have "faith" and i do beleive in us as mankind.