Hans Rosling had a way with numbers. A health practitioner, teacher and statistician, he challenged millions of peoples' preconceptions about basic issues like poverty and population growth. He did this not by giving standard power point lectures or showing endless graphs but by bringing the data to life with clever visualizations delivered with impeccable comic timing and an understated Swedish charm.
Rosling's death from pancreatic cancer at the age of 68 is a sad loss to all of us who learned from him. No lesser figures than Bill and Melinda Gates have called him a hero of our time. He will be particularly missed given how strongly the current political zeitgeist seems to be moving away from everything Rosling stood for: factual accuracy and an evidence-based worldview.
Rosling was the first to acknowledge that stats aren't everything; the world is not an Excel spreadsheet, and many things can't be best appreciated with numbers. As he told the Guardian in a 2013 interview: "My interest is not data, it's the world. And part of world development you can see in numbers. Others, like human rights, empowerment of women, it's very difficult to measure in numbers."
But in areas where the statistics are clear and the data strong, he was troubled by just how resistant first-world preconceptions could be to change. Even august audiences such as that at the American Association for the Advancement of Science annual meeting failed his test, believing that fertility rates were much higher in developing countries than is actually the case (the global average is in fact 2.4 children per woman; Rosling liked to talk about how the world has now reached "peak child").
Although his talks went viral and he became a darling of the TED/Davos set, Rosling refused to have his head turned by fame. "Fame is a dangerous thing. It's what the post-industrial society wants. They want fame and many followers on Twitter. But to really make the world understandable, that challenge is remaining," he said. Rosling's speaking fees were donated to his Gapminder Foundation, which used downloadable software so that his data visualizations could be customized and used by anyone.
As a trained health practitioner who had spent his early professional years working in Mozambique, Rosling stayed firmly grounded, and his optimism was tempered by a deep empathy about urgent health crises. In 2014, for example, in the midst of the West African Ebola epidemic, he decamped to Monrovia. For several months Rosling occupied room 319 of Liberia's Ministry of Health and Social Welfare, and worked alongside the country's head of Ebola surveillance in an effort to better understand how the epidemic was spreading and could best be controlled.
Rosling's lasting inspiration, not least to all of us at the Alliance for Science, lies in his determination not to be swayed from maintaining a fact-based worldview, and his readiness to challenge those — from whatever political perspective — who let their prejudices or ideologies get in the way of truth. In one famous exchange, he took a Swedish TV journalist to task for always talking about war and disaster and missing the bigger picture. "The facts are not up for discussion. I am right and you are wrong," he ended.
But whatever his popularity on the lecture circuit, lately it felt like Rosling was swimming against the tide. In today's era of post-truth populism, where powerful world leaders from Donald Trump to Vladimir Putin promote demagogic anti-intellectualism in order to ignore evidence and spread whatever falsehoods serve most to cement their grip on power, a voice like Rosling's is surely more needed than ever.
Tragically, Hans Rosling's candle in the darkness has gone out. Now it is incumbent on all of us to defend his legacy. Data matters. Numbers count, as does genuine expertise and scientific objectivity. The truth may have gone out of fashion for some, but that makes it even more worth fighting for.