Alhazen Gets Down To The Facts With Science
Alhazen had a lunatic boss that wanted to kill him. And you thought your last performance review was tough.
Abu Ali Hassan ibn al-Haytham (965-1040), known in the medieval west as Alhazen, was a pretty smart guy. He kinda invented the scientific method and dared to question the writings of some of the most famous ancient Greek philosophers, so of course he spent some time in jail.
Born in Basra, Iraq, Alhazen was well-known enough for his expertise in math to be invited to Egypt to lead the effort to build a dam on the Nile River. This was great news; he was excited to undertake such a prestigious project. Unfortunately, as soon as Alhazen got to the proposed job site, he realized that the Nile was too wide to be dammed with current engineering methods.
Double unfortunately, the caliph of Egypt (The Mad Caliph) was not one to tolerate failure. Instead of telling the caliph the job was impossible, Alhazen faked insanity. It was against Islamic law to execute an insane person, but it was perfectly legal to imprison them. Alhazen spent the next ten years 1011-1021 AD under house arrest in Cairo.
Sitting alone in a darkened room and away from his usual active life at court, Alhazen was bummed out, just staring at a speck of light on the wall. Turning those lemons into lemonade, he started investigating the nature of light. He experimented with the ways light was reflected, concluding that rays traveled in straight lines.
Basing his conclusions on his experimental results, he wrote the Book of Optics, his most famous work. It was translated into Latin in the late 1100s and became a foundational text for future scientific inquiry.
While Book of Optics doesn’t sound like a controversial title, his work contradicted the writings of Euclid and Ptolemy, the ancient Greek thinkers. They believed in emission theory, the idea that light shoots out of your eyes and lands on an object that you see.
Aristotle believed in intromission theory, where light enters your eyes and enables you to see. Alhazen’s experiments proved that light does not shoot out of your eyes. He even updated the writings of Galen about the anatomy of the eye: retina, cornea, and lens. You’ve seen the poster at your list visit to your optometrist. Alhazen sketched it first.
Alhazen also wrote about the moon illusion, the way the moon and the sun appear to be larger when they are near the horizon than when directly above you in the sky. Alhazen said that it was an optical illusion, which is what NASA says too. You can go outside, look up, and see this illusion today. If you do, check out the moon, but don’t look directly at the sun. To repeat, even if you are president of the United States, do not look directly at the sun.
While it’s an overstatement to say that one person invented science, Alhazen’s experimental methods are still the ones used today - hypothesis, test, results, conclusion - just like your third grade science fair project.
Alhazen not only made contributions to science with his experimental method, the method itself is what you call the scientific method. For all his efforts, the Alhazen crater on the moon is named after him, which is pretty cool.
Today, the name of al-Haytham is not nearly as famous as that of Galileo or Newton, but those guys used his Book of Optics as the foundation for their own work.
Also, most online resources today use his Arabic name, al-Haytham, not Alhazen, the name he was known by all medieval scholars in the west. Sometimes it’s spelled Alhacen, so he’s a hard guy to google. There’s probably a lesson about branding in there somewhere…
The most important lesson from Alhazen’s life and career is to get to the facts, not just accept received wisdom. In the year 1020, anyone who knew anything knew that Galen, Ptolemy, and Euclid were the experts. Their writings had been trusted for hundreds of years. By conducting his own experiments, Alhazen proved them wrong on a few points.
There are experts at your company, in your industry. They probably know what they're talking about. But are they infallible? Probably not. If you’re going to disagree with the experts in your field, you’ve got to have facts and data, not just passion and opinions.
You might be right. So prove it. Respect the facts. Bring data to your argument and see how much more powerful it becomes. You might even sway the opinions of your crazy boss.
