Science is great, but individual scientists are dangerous – Nassim Taleb
Lord Kelvin is one of the most prodigious scientists to walk the earth. Kelvin was admitted to the Glasgow University at the age of ten, and since the age of twenty-two, he held a professorship in natural philosophy. He wrote 661 papers and gathered 69 patents. Among others, his contributions include:
– Inventing refrigeration
– Devising the scale of absolute temperature
– Enabling telegrams to be sent across oceans
– Inventing a modern mariner’s compass
The one shortcoming in his otherwise illustrious career was his inability to calculate the age of the Earth. Kelvin spent much of the second half of his career engaged with this question, but never came anywhere near the right answer. His first estimate was 98 million years, while admitting it could be as low as 20 million or as high as 400 million. Through the course of his life, Kelvin became more assertive about his estimates. He revised the maximum number downwards from 400 million years to 100 million. Later, he put the number at 50 million years, and finally in 1897, about 10 years before his death, he asserted that the Earth was, at most, 24 million years old. Alas, he was far too wrong. Today, we know the Earth to be about 4500 million years old.
In 1904, a brilliant young scientist from New Zealand called Ernest Rutherford made a landmark finding. He presented new evidence to Lord Kelvin that a sample of uranium he had analysed was 700 million years old – way older than Kelvin’s estimate for the age of the Earth. Knowing that he was in the presence of a scientific giant, Rutherford was tactful and respectful in getting this message across. Lord Kelvin beamed at his presentation, but was unmoved by its argument. To his dying day, Kelvin didn’t believe the revised figures and went to his grave with the assumption that his most important contribution to science was his work on finding the age of the Earth.
The German physicist Max Planck said that science advances one funeral at a time. Pierre Azoulay and his colleagues recently investigated this assumption and found it to be true based on publications made in a field, and their likelihood to be cited. “The loss of a luminary,” they write, “provides an opportunity for fields to evolve in new directions that advance the frontier of knowledge.”
Although science itself is a field that is dedicated to the impartial and unequivocal pursuit of rational truth, the scientists who further it are human. And with humans, scientific or not, the emotional tail wags the rational dog. Therefore, in our worlds of emotional human decision makers, we need systems like the scientific method to ensure that the pursuit of the truth is not forestalled by our tendency to hold on to our truth.