Isegoria

Science asked its readers what one piece of scientific knowledge from today they would share, if they could go back in time, and how might it change the course of history?

The responses show an almost laughable ignorance of the real world:

If I could travel back in time, I would transport to Syracuse, Sicily, in 222 B.C.E. to introduce the fundamental theorem of calculus to Archimedes 10 years before his death. As the great mathematical genius of his era, he would have been most poised to understand and disseminate the knowledge of linking the concept of a derivate of a function with the concept of the integral.… So much technology of today, from the internal combustion engine to the principles of economics, has been made possible due to calculus.

The internal combustion engine was made possible due to calculus?

As the future scientific envoy, I have an audience with Emperor Qin and present my gift: Women are capable of doing the same thing as men; they even can do better. Certainly, with adequate data, glorious accomplishment stories, and plenty of examples, such as Madame Curie, Mrs. Thatcher, Deng Yaping, and Oprah Winfrey, I can convince Emperor Qin to give women more chances to receive education and give full play to their talent in science and technology, culture, politics, and the military. In that way, more than 2000 years later, China would surely be a super power stronger than today.…

Yeah…

I would go back to ancient Rome on the morning of 15 March, 44 B.C.E., to the steps of the Roman Senate, and share Bayes’ Theorem with Julius Caesar. In the days leading up to his assassination, Rome was awash with rumors of an assassination plot. According to legend, an old soothsayer had forewarned Caesar himself of a great danger that threatened him on the Ides of March, and Caesar’s own wife Calpurnia had a premonition of her husband’s murder and tried to warn him of the danger. But were these dark forebodings and dire prophecies just idle gossip (noise) or a credible forecast of the future (signal)? Given this uncertainty, I would advise Caesar to guess the prior probability of an assassination plot and then update his prior based on the sundry rumors swirling around Rome. Had Caesar applied Bayesian reasoning, it is likely he would have followed his wife’s advice and stayed home on that fateful day. Had he done so, Bayes’ Rule might have changed the course of history, for the Roman Republic might have yet been saved, and perhaps we would all still be speaking Latin.

Riiiiggghhht.

In 1687, Sir Isaac Newton published his Principia outlining the fundamentals of what quickly became called Newtonian mechanics. I would travel back to Cambridge, England, 5 years before this date and teach Einstein’s, theory of relativity to Isaac Newton. The obvious change in history resulting from this action would of course be a massive head start for the field of modern physics.… However, I would argue that a less obvious but possibly more important consequence of this historical change would be its effect on how we teach science. Currently, high school students and first year undergraduates are taught the limited version of physics discovered by Newton. Only students who choose to continue in the discipline learn Einstein’s more generalized form of mechanics and how classical mechanics is encompassed in this modern understanding. If Newton had discovered both his and Einstein’s contributions at the same time, the result would be an educational system that introduces a more complete view of physics to a wider audience of people from an earlier age.…

You see, more people would move beyond simple Newtonian physics, if only Newton had understood relativity! Clearly!

Instead of a piece of technical knowledge, I would share something that would provide perspective: the photo of Earth taken by the Apollo 17 astronauts in 1972. “The Blue Marble,” as it is often called, shows both the unity and finitude of the planet and its resources. The photo is emblematic of the modern environmental movement’s birth in the 1970s. I would bring this photo to early 19th-century Britain, during the Industrial Revolution, when consumption of Earth’s resources began to increase dramatically. Providing this information 150 years earlier would be an opportunity for the soon-to-be industrialized culture of western Europe to reconsider its relationship with the planet.

I’m sure early 19th-century Britain would react to the photo in the exact same way as late 20th-century America.

“Hello, Professors [Svante Arrhenius and Arvid Högbom], I travel back in time from 2013 to tell you that…since the early 20th century, Earth’s mean surface temperature has increased by about 0.8°C. The primary cause is greenhouse gases produced by human activities. The Intergovernmental Panel on Climate Change indicated that during the 21st century the global surface temperature is likely to rise another 1.1°C to 2.9°C, even for their lowest emissions scenario. Global warming isn’t just about things getting hotter; other changes include stormier, drier, and even colder conditions.” The next day, they wrote to the government and the scientific associations to call people’s attention to global warming and adaptations to eliminate it. Actions like reducing fossil fuel use, planting trees, and conserving water were known by people all over the world. Instead of destroying the planet, every single man on Earth began to protect and sustain it in their daily life.

I can imagine the swift Swedish reaction to the threat of mildly warmer temperatures.

I would choose Thomas Edison in the beginning of the year 1900 in New York City. I would describe the events of the future and how he and I could help keep our environment cleaner. I would give him designs to solar panels and hope that the future of solar technology would make America and other countries independent of oil production. Thomas Edison’s name alone could create Edison Panels that would be on every Victorian home in the world, especially in hard-to-reach locations…. Fewer trees would be cut, and the world would remain more rural and yet prosper from a new power source.

Edison supposedly did recommend harnessing the sun’s energy, for what it’s worth. Solar-thermal energy might be practical early in the Industrial Revolution, but photovoltaic would be a long, long way off.

I would be inclined to bring the Romans knowledge of movable type and paper, or maybe glasswork and lenses. I’m not sure that you can do much with an understanding of the heliocentric solar system, the periodic table, evolution, etc.

A recent study has linked pesticide exposure and depression in male private pesticide applicators — or farmers:

There’s a significant correlation between pesticide use and depression, that much is very clear, but not all pesticides. The two types that Kamel says reliably moved the needle on depression are organochlorine insecticides and fumigants, which increase the farmer’s risk of depression by a whopping 90% and 80%, respectively. The study lays out the seven specific pesticides, falling generally into one of those two categories, that demonstrated a categorically reliable correlation to increased risk of depression.

These types aren’t necessarily uncommon, either; one, called malathion, was used by 67% of the tens of thousands of farmers surveyed. Malathion is banned in Europe, for what that’s worth.

I asked whether farmers were likely to simply have higher levels of depression than the norm, given the difficulties of the job — long hours, low wages, a lack of power due to government interference, that kind of thing — and, according to Kamel, that wasn’t a problem at all. “We didn’t have to deal with overreporting [of depression] because we weren’t seeing that,” she says. In fact, only 8% of farmers surveyed sought treatment for depression, lower than the norm, which is somewhere around 10% in this country.