The most important technologies that no one is working on are optimism and beautiful visions of the future. A belief in technological progress must include giving people places and futures worth believing in. It doesn't come for free.
Optimism makes you less likely to walk away while not actually increasing your chances of success. That means that being overly optimistic will make you stick to things longer that aren’t worthwhile. Better to be well calibrated. Life’s too short to spend your time on opportunities that are no longer worthwhile.
It took me a while, but I eventually figured out what he meant. Sometimes the task of rebuilding—of accepting what has been broken and making things anew—is so daunting that it can almost feel easier to believe it can’t be done.