User:Pgs4748/sandbox

Ibn Al Haytham had an important and impactful role in the optics world, his scholarly work is considered to still be in use in present-day and is at times is connected to modern optometry. Haytham was born in Basra, Iraq in 965 and later died in Cairo, Egypt in 1040 (Lorch, 2017). The specific and small details about his life are not clear and many say that they have been lost over time, but the important details remain and those have been what have influenced more work today. In his lifetime, Haytham had many pieces of work to which he dedicated his time and efforts. He was commonly known as a mathematician and astronomer, but this was not all he was recognized for. His contributions in his work ranged further than that to pieces that had no attachment to math or astronomy. Haytham wrote over two hundred pieces over a wide range of subjects, and out of those, it is said that ninety-six were commonly known. However, over the years only fifty of them survived and can be found to this day (Tbakhi, 2007). Some of the most significant and commemorated pieces of work however are attached to optics and light. Out of these pieces of work, these are included the Kitab Al Manazer “Book of Optics”, Risalah fi al-Dawa’ “Treatise on Light”, and Mizan al-Hikmah “Balance of Wisdom” (Tbakhi, 2007). These are some of the pieces that emphasized and theoretically changed the way of thinking in regards to vision. The way Haytham approached this new way of thinking also brought light to the methods that he used in the process. These of which have later been associated with the famous and widely known Scientific Method. His methods of investigating vision and optics, the approach with using experiments to test these methods, and the results have a very similar approach to the modern-day scientific method that is widely used in research (Tbakhi, 2007). Out of all of these works that Haytham wrote, however, Optics was the most influential in various places around the world. His approach to learning and understanding vision and optics revolved around the new and unaccepted idea that light does not originate from the eye, but rather it enters the eye to have an effect on vision (Masic, 2008). The previous theory to a vision that had originated and been accepted came from Galen, a Greek physician. In a book written by Cherniss, “Galen and Posidonius' Theory of Vision” this theory is explained (Cherniss, 1933). The main difference between the theory that Galen proposed versus the one that Hytham proposed was the way that light was involved. In Galen’s theory and approach, the way vision worked as a medium of touch. In this manner, the air was the medium that helped it be perceived. Therefore, the theories were in an ironic manner contradicting each other in regards to the explanation as to how this phenomenon took place. Getting more in-depth with Haytham’s approach to vision, however, and some of the methods used in his famous piece, “Optics”. His work has focused on understanding and applying the laws of reflection that had not been understood to their full capacity in the past by the various scholars who had attempted to understand and explain how this took place. As stated before, his approach to vision involved the reflection of light into the eye, versus the previous methods that involved light leaving the eye (Evans, 2019). By understanding reflection, Haytham was able to turn the old theory around and include the approach of light and outside objects. These extraneous objects had an effect on how the light was perceived, which in the end had an effect on how it was seen. Another major incorporation to this new theory was the investigation and application in understanding refraction. Haytham was able to understand how light moves in different mediums and applies this to his theory and his new way of thinking about vision and light (Evans, 2019). Refraction had been included in a way in Galen’s theory in regards to air, but Haytham took a new approach to it. As mentioned before, this theory that we use and accept in modern-day was not initially accepted by those around Haytham. It was not until the piece, “Optics” was translated into Latin in the twelfth century (Razaullah, 2018). It was not until after this occurred that it was noted to begin having an impact on others, and we began to see commentary on his theory. Roger Bacon is one of the examples that we can attribute to having incorporated Haytham’s theories and thoughts into his work as well. There are many examples in his work that attribute Haytham and his discoveries to further understand and develop his own. For example, he follows Haytham and imposes a geometrical model of the eye that he would not have been able to do in the same manner without that influence (Hackett, 2013).

Bibliography Evans, James, and Michael Wulf Friedlander. “Astronomy.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 31 Oct. 2019, www.britannica.com/science/astronomy. Accessed on 11/19/19 Cherniss, Harold. “Galen and Posidonius' Theory of Vision.” The American Journal of Philology, vol. 54, no. 2, 1933, pp. 154–161. JSTOR, www.jstor.org/stable/290071. Accessed on 11/19/19 Hackett, Jeremiah. “Roger Bacon.” Stanford Encyclopedia of Philosophy, Stanford University, 11 Nov. 2013, plato.stanford.edu/entries/roger-bacon/. Accessed on 11/19/19 Lorch, Richard. “Ibn Al-Haytham.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 1 Feb. 2017, www.britannica.com/biography/Ibn-al-Haytham#ref729295. Accessed on 11/19/19 Masic, Izet. “Ibn Al-Haitham--Father of Optics and Describer of Vision Theory.” Medicinski Arhiv, U.S. National Library of Medicine, 2008, www.ncbi.nlm.nih.gov/pubmed/18822953. Accessed on 11/19/19 Tbakhi, Abdelghani, and Samir S Amr. “Ibn Al-Haytham: Father of Modern Optics.” Annals of Saudi Medicine, King Faisal Specialist Hospital and Research Centre, 2007, www.ncbi.nlm.nih.gov/pmc/articles/PMC6074172/. Accessed on 11/19/19 Razaullah Ansari, Shaikh Mohammad. “Ibn Al-Haytham's Scientific Method.” UNESCO, 15 May 2018, en.unesco.org/courier/news-views-online/ibn-al-haytham-s-scientific-method. Accessed 11/19/19