Billionaire Bill Gates shares 7 reasons to feel good about humanity in 2017

In many ways, 2017 has been a difficult year: Hurricanes left much of Houston underwater and ravaged the Caribbean and Puerto Rico, fatal wildfires quickly spread across several parts of California and concert goers lost their lives in Las Vegas, to name a few.

But there are also things to be optimistic about and Tuesday billionaire Bill Gates highlighted a handful of moments to inspire from this year.

1/ There's no denying that 2017 was a really tough year... but it also delivered some amazing moments of hope and progress. Here are some inspiring tweets that you may have missed…

2/ On May 18, 2017, Edwardo Sanchez tweeted that he was the first person in his family to graduate from college. Congratulations, Edwardo!

On May 18, 2017, I became the first person in my family to graduate from college!

3/ "Toilet: A Love Story," a Bollywood romance about a newlywed couple, educated audiences about India's sanitation challenge.

'Toilet, a Love Story': Bollywood spotlights India's sanitation crisis in new film

4/ In June, the WHO certified that Bhutan and Maldives had eliminated measles.

Bhutan and Maldives eliminate measles

5 /2017 World Food Prize winner akin_adesina will use his prize money to establish a fund to provide grants to African youth involved in agriculture.

The World Food Prize gives me greater zeal to feed Africa and end hunger in our world. No resting until we succeed!

6/ The New York Times reported that doing good for others helps those who give as well as those who receive.

7/ A new sport caught on in schools to encourage students to read. It's called #extremereading.

Well done to 6yo Zackary Howells on his #ExtremeReading award!

8/ Here's my own extreme submission to the challenge. #extremereading

9/ These tweets made me feel better about 2017 and more optimistic about the new year. I hope they make you feel more hopeful, too. What tweets inspired you this year?

Gates isn't the only billionaire to recognize the importance of optimism. Facebook founder and CEO Mark Zuckerberg says it's the optimists among us who are successful.

"One of my favorite sayings is that there are two kinds of people in the world: optimists and pessimists. And the saying goes that optimists tend to be successful and pessimists tend to be right," says Zuckerberg, addressing nonprofits in November.

"And the idea is that if you think something is going to be terrible and it is going to fail, then you are going to look for the data points that prove you right and you will find them. That is what pessimists do …

"But if you think that something is possible, then you are going to try to find a way to make it work. And even when you make mistakes along the way and even when people doubt you, you are going to keep pushing until you find a way to make it happen," Zuckerberg says.

See also:

This favorite saying of Mark Zuckerberg reveals the way the Facebook billionaire thinks about life

Facebook CEO Mark Zuckerberg: Elon Musk's doomsday AI predictions are 'pretty irresponsible'

What Facebook CEO Mark Zuckerberg is more afraid of than screwing up his $438 billion company

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