Elon Musk has sold around $5 billion of his stock in Tesla shortly after he ran a Twitter poll asking if she should sell it, regulatory filings reveal. That, in turn, followed a conditional offer to donate $6 billion to solving world hunger – there are no reports yet of an actual donation, and there is evidence Musk was planning to sell for other reasons. Much of the money will be required to pay a recent tax bill, but perhaps public pressure will convince Musk to send some of it towards fulfilling his promise.

As a general rule, it's a bad idea to base major life decisions on a social media poll – particularly on Twitter, where voters may well not be your friends. Nevertheless, when your shares and options in a company are valued at $240 billion, maybe selling 4.5 million of them isn't too major in the grand scheme of things. This amounts to 3 percent of Musk's Tesla stake, in addition to his holdings in other companies. However, it could be a major decision for the world if he follows through with the (again tweeted) offer to donate to hunger prevention.

A combination of pandemic-induced obstacles to trade, natural disasters made worse by global heating and wars has caused a sharp increase in the number of people undernourished worldwide after years of decline. David Beasley, director of the Nobel Prize Wiining United Nations World Food Program (WFP), has made increasingly pointed calls for billionaires, particularly Musk and Jeff Bezos to “step up now, on a one-time basis” to address the problem.

Musk responded with a since-deleted tweet; "If WFP can describe on this Twitter thread exactly how $6B will solve world hunger, I will sell Tesla stock right now." The wording of his message was ambiguous. Did the WFP need to show this money could wipe out hunger entirely – a task for which $6 billion is unlikely to be even temporarily adequate – or just to show it could make a measurable difference?

A week later Musk ran a Twitter poll asking:

The sale followed, but correlation is not always causation.

So far the UNWFP hasn't reported receiving the money, or even providing a plan to meet Musk's demand on how they will spend it

Traditionally most of the WFP's roughly $8 billion budget comes from the governments of wealthier countries. Few, however, have indicated they would increase their contributions to match the current crisis.

The WFP has said it needs $6.6 billion, on top of existing funding, to address the needs of those currently on the brink of famine. That certainly won't eliminate hunger entirely – solving world hunger is likely to follow the Pareto Principle where the last 20 percent takes 80 percent of the effort. However, if Musk comes through, it will mean millions of people will survive who might otherwise die, and tens of millions more will be spared lifelong damage. If other billionaires are convinced into following, the impact could multiply.