I can't really fathom why anyone would care what his reasons are. He wants to give away several billion to improve education and eradicate disease and poverty, and beyond that reasons really shouldn't matter.

Carnegie's philosophy on wealth (mentioned in the article) is not a terrible philosophy to live your life by both in the realm of philanthropy and in most other aspects of life.

You should read How To Get Rich by Felix Dennis. Here is an excerpt where he mentions giving money away: "So why do I not give it away? Because I worked too hard for it. Because I am tained by it. Because I am afraid to. All those reasons and more. Perhaps, if I am lucky enough to become old, I will accumulate something else: the courage to give it all away before I die. That would be a good thing, I think. ... "Giving money away when you are dead takes no guts. No courage. But to divest yourself of hundreds of millions of dollars, or the greater part of your fortune, before your death? That would be something to be proud of, don't you think? It even makes logical sense."

> Why get a fortune just to give it away?

Why climb Mount Everest just to come back down?

I think that for some people, particularly billionaires, money is more about keeping score.

A commonly reiterated finding is that, while having more money can indeed contribute towards a happier life, it only does so to a point. According the the article, Zuckerberg's speculatively worth roughly $6B; if this proves accurate and he gives 90% of that away, he's still sitting on a small fortune. I'd hope that he is capable of figuring out how to make do with "only" $600M or so.

To shape the world.