Tricky isn’t it, when you find yourself suddenly locked in a chemical laboratory and asked to turn transparent a purple potassium permanganate solution found in one of the beakers. When you have absolutely no idea what to do, you just don’t mix things gung-ho and expect a good outcome. That just calls for a calamity. Things go boom. Toxic gasses fill the room. The birth of a new species. The accidental emergence of a black hole. Stuff happens. You need a plan and an idea of how basic chemistry works to conduct this experiment successfully. Ok, let’s do it. Make the potassium permanganate solution acidic first by adding hydrochloric or sulfuric acid. Next, pour a significant amount of hydrogen peroxide to the mixture then it’ll turn transparent. You just did science. Nice.
Science operates on failures and successes. Both are outcomes of an ideal standard on how to do science. A plan of action and a guiding idea called a hypothesis are the basic elements of what we call the scientific method. But like any human program and process, it didn’t just pop out of nowhere. It has a history. And what is commonly said of the scientific method’s history is that its origins can be traced to Francis Bacon who fried up this crispy new way of thinking in his Novum Organum Scientiarum. In it, he champions the flavor of induction over syllogism and details the recipe of his method. That is what popular history tells us.
However, if one applies the scientific method to the history of the scientific method, one finds that what popular history shows us is just a small bite of a larger meal. Bacon’s contributions to the development of science is indisputable. But his place as the originator of a method, the scientific method, is questionable. Because for centuries and centuries before him, a Muslim scholar under Egyptian surveillance advocated for a method in doing natural investigations. He did so while trying to illuminate the then dim department of optics.
Born in the Iraqi city of Basra, Ibn al-Haytham (965- 1040), or Abū ʿAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham for short, was a man of many things – mathematician, astronomer, physicist, translator, and madman. Well, the last one deserves speculation. Little is known of his early life in Basra. Much of what is known about Ibn al-Haytham comes from the Arabic historian Ibn al-Qifti, who wrote of Ibn al-Haytham’s mad episode. An imbroglio which, arguably, led to his greatest achievements.
After hearing rumors of a man having a plan to build a dam on the Nile to regulate its floods, the Egyptian Caliph al-Hakim of the Fatimid dynasty sent out emissaries to have him come to Egypt to confirm his ballyhoo. That man was Ibn al-Haytham. Upon arriving in Egypt, he peered and perused the Nile which he had never seen before and realized what a massive blunder he had just made. It was far too impossible an ordeal. Current engineering technology and techniques just weren’t enough to temper the Nile. And it wasn’t even the Nile’s potent power that was the biggest concern in this gaffe. A far more sinister danger reared its head. It was the potentate. The Caliph was known for his mad unpredictable episodes (in one instance he ordered the killing of dogs because their barking annoyed him) and al-Haytham knew he was in trouble for his grandstanding. To escape punishment for his peccadillo, al-Haytham devised a clever plan: if the Caliph was a bit mad then the only way to dodge disaster would be to out-mad him! This was a rash, reckless, and ultimately ridiculous plan, and surely an insult to the ornery Caliph. But fortune works in mysterious ways: the plan actually worked and Ibn al-Haytham was spared from cruel comeuppance. The Caliph only ordered to have him under house arrest. Well played.
While his legs couldn’t take him far since his failure fettered him immobile inside his home, there was nothing to stop Ibn al-Haytham’s eyes from broadening his vision. Particularly in optics. At that time, the central tenets of optics were shaped by the views and writings of Euclid, Galen, and Ptolemy who argued in strength for the emission theory of vision. The idea is that the eye functions as a light-emitter. Like a flashlight that illuminates objects to make them visible. Back then Christmas lights were just children asked to blink nonstop by their parents. Which is probably why Santa Claus gives them toys to recompense their labor of light. Fortunately, Ibn al-Haytham was not a kid anymore, nor did he celebrate Christmas, thus he was able to see something wrong in this theory. The Christmas lights conundrum presented one problem, because the idea of Christmas lights hadn’t existed yet. The problem involving mirrors was another: if I look in the mirror, I see myself because the mirror reflects my image and the light coming from my eyes makes my reflection visible; however, why is it that I don’t squint my eyes like I do when I look at a source of light like the sun? In fact, the sun was a bigger issue: if humans looked at it collectively, why is it that the sun does not get outshined, instead, it makes humans go blind?
Ibn al-Haytham had an idea. The correct one. He knew light didn’t come out of our eyes. In fact, the opposite is true: light enters our eyes. Ibn al-Haytham, cautioned by his earlier Nile howler, decided to take a more measured approach in forwarding this idea, and in doing so, revolutionized natural investigations. His contention against the emission theory came in the form of a seven-volume text, titled Kitab al-Manathir or Book of Optics. His approach was to reinforce his beliefs with mathematics and experimental results, that is, he developed a method for doing science – historians say he is the first person to ever do so. Since he believed that light came from external sources and not from the eye, he devised an experimental set-up that not only showed how vision works, but also demonstrated one fundamental aspect of light. For this experiment, Ibn al-Haytham devised a camera obscura, or a dark room, to project an image using a really small hole into a room with no light. Think of a fascist box the size of an average bedroom that permits no light inside it. Now, bore a small hole on one of its sides to forcibly allow light to enter. On the opposite side of the hole inside the box, an image of the outside world is projected, but turned upside-down. Why is that so? Ibn al-Haytham explains that it is because light comes from an external source and that light travels in straight lines. In both counts, he was correct. The emission theory of light was now out of sight.
Having provided the necessary corrective in optics, Ibn al-Haytham looked to other academic fields where he could shine his light. He was one of the first to successfully integrate algebra and geometry, paving the way for analytical geometry. From his Ptolemaic grounding, he also developed and improved current ideas on refraction and reflection, though it would take centuries for these ideas to arrive at the correct conclusion at the hands of Isaac Newton. The breadth of his work even included early attempts at ophthalmology as he took notes from Galen and gave his own advice on how to prevent eyesight damage. All these from a man who was supposed to be mad. A madman who instantly got better once the Caliph suddenly disappeared in 1021.
After his release from incarceration, Ibn al-Haytham decided to remain in Egypt for the rest of his life. Freedom didn’t make him lose sight of his scientific ambitions, and he continued to pursue scientific research until his death in 1040. He managed to write more than 200 books, wherein 96 of which discussed scientific subjects. A truly impressive body of work. What is often overlooked when recounting his contributions, however, is his contribution to pranking and tomfoolery. After all, he built himself a solid scientific career after saying:
It was just a prank, Caliph.
Al-Khalili, Jim. (2015). Book of Optics. Nature, 518. 164-165
Al-Khalili, Jim. The house of wisdom: how Arabic science saved ancient knowledge and gave us the renaissance. London, UK: Penguin Books. 2012
Lindberg, David. Theories of vision from Al-Kindi to Kepler. Chicago, USA: University of Chicago Press. 1996