There are some scientific truths that are so simple and obvious, it's hard to imagine a time when people didn't believe in them. Just as people once believed the Earth was flat, it was also widely accepted that our planet was the center of the universe with the sun and planets revolving around us.
As astronomers began making detailed observations of the night sky, it became clear that geocentrism had to be wrong. Nicholas Copernicus published his unprecedented theory of a universe with the sun at the center (heliocentrism) just before his death in 1543. Other astronomers continued to build on this work, with the most famous being Galileo Galilei.
Unfortunately, this idea angered the powers that be.
The idea that the Earth was not the center of the universe went directly against the teachings of the Catholic Church, as certain passages in the Bible that referenced the Earth being immoveable were taken literally. Galileo's teachings contradicted that idea, putting him on trial during the Roman Inquisition.
Pope Paul V decided in 1616 that Galileo must renounce his heliocentric beliefs and stop teaching them or end up in jail. On February 26, he chose to stay out of jail, though he still privately believed in the theory.
The image below shows the difference between a solar system with the sun in the middle, versus one with the Earth in the center.
In a geocentric system, the other planets would have to have ridiculously confusing orbits in order to match up with their observed positions relative to Earth.
It simply cannot be.
Over the years, Galileo's promise not to teach heliocentrism began to slip, and he published work that didn't outright advocate heliocentrism, but was enough to get him convicted of heresy charges in 1633. While he didn't go to prison, he did spend the rest of his life under house arrest.
By the end of the century, decades after Galileo's death in 1642, the heliocentric model was widely accepted, and he would ultimately be pardoned by Pope John Paul II in 1992.
It has been 400 years to the day since the Vatican forced Galileo to renounce heliocentrism or face prison. Though his name has been cleared, scientists have continued to struggle to make important discoveries accepted.
Charles Darwin's theory of evolution through natural selection was not well-received at first. In the years that followed, scientists would collect more fossil and genetic evidence to support evolution than Darwin could have ever dreamed existed. Yet, many people still reject the evidence and fight to keep it from being taught in classrooms.
There is an overwhelming amount of evidence to support that vaccines are safe and effective, though people continue to perpetuate disease by opting out of them and spreading misinformation rooted in ignorance and fear.
Perhaps the biggest struggle scientists have today is convincing people that man-made climate change is a global threat unlike anything humanity has seen before. While mankind should be united in making aggressive changes to minimize the predicted effects, too many are rejecting the evidence.
Instead of making progress, we're wasting time we don't have.
Galileo's case proved that scientific truths don't just go away because they're unpopular or challenge received ideologies. It isn't always easy to accept being wrong, but continuing to discover, learn, and grow is the only way progress can ever be made. No amount of clinging to ignorance will change that.
Perhaps Galileo himself said it best:
"In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual."
Cover image: Michael Schall/A Plus