Came across this quote today. One worth memorizing.
In the face of all the challenges we face today, is my optimism about the future of humanity idealistic? Perhaps it is. Is it unrealistic? Certainly not. To remain indifferent to the challenges we face is indefensible. If the goal is noble, whether or not it is realized within our lifetime is largely irrelevant. What we must do therefore is to strive and persevere and never give up.
—Dalai Lama