"If our optimism doesn't address the problems that affect so many of our fellow human beings, then our optimism needs more empathy. If empathy channels our optimism, we will [address] the poverty and the disease and the poor schools."
The problems the graduates choose to focus on will determine whether the world gets better, he said.
"If your world is wide, you can create the future we all want. If your world is narrow, you may create the future the pessimists fear," Gates said.
"As I started learning in Soweto, if we are going to make our optimism matter to everyone and empower people everywhere, we need to see the lives of those most in need. If we have optimism without empathy, it doesn't matter how much we master the secrets of science. We are not really solving problems," he said. "We are just working on puzzles."
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