‘Science can explain what exists in the world, how things work, and what might be in the future. By definition, it has no pretensions to knowing what should be in the future.’ So wrote Yuval Noah Harari in Sapiens. He gets it. As does 18th-century Scottish philosopher David Hume, who intuited that material reality cannot determine moral reality in his famous ‘No Ought From Is’ principle.
A handful of other people have made similar points during the Covid-19 pandemic. Here’s Dr Vinay Prasad, associate professor of epidemiology and biostatistics at the University of California in San Francisco: ‘Science cannot make value judgments. Science does not determine policy. Policy is a human endeavour that combines science with values and priorities.’ With respect to the school-closure debate, Prasad noted that:
‘Science can help us quantify the increased risk (or lack thereof) of school reopening on SARS-Cov-2 spread, and help quantify the educational losses from continued closure, but science cannot tell you whether to open or close schools. Making the decision requires values, principles, a vision of the type of society we want to be.’
Erman Sozudogru, a teaching fellow in philosophy of medicine at UCL, reached the same conclusion early on in the pandemic. ‘While scientists are working around the clock to enhance our understanding of this disease’, he wrote in March 2020, ‘there is no conclusive data that can determine the best method to combat Covid-19. What drives decisions is our value judgements.’
Unfortunately, such insights haven’t penetrated the zeitgeist. Instead, experts and media pundits alike have spent the past year exhorting us to ‘follow the science’, as though science came with a roadmap and moral compass.
Science gives us information, not instructions. It’s a bit like a weathervane. You can look at a weathervane and deduce that there’s a stiff wind coming in from the north-west. What the weathervane can’t tell you is how to respond to the information. One person may decide it would be mad to step outside on such a windy day, while another may conclude it’s the perfect day for a bracing walk. Same input, different responses.
If you’ve decided to step into the wind, science can help you figure out how to stay warm. For example, science tells you that air-trapping materials, such as goose feathers, do a superior job of conserving heat. Science tells you that wearing a hat can help your feet stay warm. But science cannot tell you whether to take that windy walk or sip hot cocoa on your sofa while watching the trees slap against the window panes.
To put it another way: science can tell us how to reach a goal, but it cannot tell us what goal to reach for. That job falls to ideology. To ethics. To values. Here’s Harari again, this time in a February 2021 Covid retrospective in the Financial Times: ‘When we come to decide on policy, we have to take into account many interests and values, and since there is no scientific way to determine which interests and values are more important, there is no scientific way to decide what we should do.’
In other words, ‘follow the science’ does not hold up to logical scrutiny – whether the science is robust or shaky, established or in flux. When people say ‘follow the science’, what they really mean is ‘follow my values’.