Despite wars, disease and climate change, billionaire Microsoft co-founder Bill Gates says he's optimistic that humans' lives will continue to improve.

Posting on his blog last Thursday, Bill Gates shocked the philanthropic world with a stunning announcement: the Microsoft co-founder will accelerate his plans to give away almost all of his wealth over the next 20 years. He vowed to reduce his net worth ...

Despite global turmoil, Bill Gates believes humanity is on the cusp of remarkable progress. From cutting child mortality to eradicating deadly diseases, his $200 billion plan aims to reshape the world in 20 years.