Renaissance in Human mind and history Islamic Golden age: IX-XVI Islamic Golden Age – had enormous contribution to the history of human kind. Philosophers and scientists of the G.A not only preserved the earlier traditions but added their own inventions and innovations to the science, technology and culture. The tradition of the pilgrimage to Mecca, made the Mecca a center of exchange for ideas and goods. The influence held by Muslim merchants over African-Arabian and Arabian-Asian trade routes such as historical Silk-Road was huge. Therefore, Islamic civilization expanded on the basis of its merchant economy, in contrast to their Christian, Indian and Chinese peers who built societies from an agricultural landholding tradition. Among the major achievement of Muslim scholars during the G.A were the developments of trigonometry, mathematics, philosophy, astronomy, politics, optics architecture and engineering into its modern form. Also, medicine was a central part of an Islamic culture. Responding to circumstances of time and place, physicians and scholars of the Golden Age developed complex medical literature and practice. Islamic medicine was built on chiefly on knowledge developed in Greece, Rome and Persia. For Islamic physicians Galen and Hippocrates were the main authorities. In order to make Greek tradition more accessible and teachable, Islamic scholars translated and developed the works of Greek scientists by writing encyclopedias and summaries in Arabic. In philosophy Ibn Rushd and Persian polymath Avicenna played a major role in saving the works of Aristotle, whose ideas came to dominate the non-religious thought of the Christian and Muslim worlds. Three speculative thinkers, al-Kindi, al-Farabi, and Avicenna, combined Aristotelianism and Neoplatonism with other ideas introduced through Islam. Controversy It has been and still continues to be very controversial the importance of the Golden Age. Some historians and scholars called it a myth, intended to popularize the religion Islam.  A disputing fact for that was an existence of such influential scientist – Plymouth Avicenna, who wrote almost 450 treatises on a wide range of subjects: philosophy, astronomy, alchemy, geology, psychology,  Islamic theology, logic, mathematics, physics, as well as poetry of which around 240 have survived. In particular, 150 of his surviving treatises concentrate on philosophy and 40 of them concentrate on medicine.  His most famous works are The Book of Healing, a vast philosophical and scientific encyclopedia, and The Canon of Medicine, which was a standard medical text at many medieval universities. The Canon of Medicine was used as a text-book in the universities of Montpellier and Leuven as late as Canon of Medicine provides a complete system of medicine according to the principles of Galen and Hippocrates.  Ulugh Beg was notable for his work in astronomy-related mathematics, such as trigonometry and spherical geometry. His own particular interests concentrated on astronomy, and, in 1428, he built an enormous observatory called the Gurkhani Zij. Lacking telescopes to work with, he increased his accuracy by increasing the length of his sextant, had a radius of about 36 meters (118 ft) and the optical separability, of 180" seconds of arc.  Using it, he compiled the 1437 Zij-i-Sultani of 994 stars, generally considered the greatest star catalogue between those of Ptolemy and Brahe.  In 1437, Ulugh Beg determined the length of the sidereal year as as 365 d 5 h 49 m 15 s, which has an error of +25 s, making it more accurate than Copernicus' estimate which had an error of +30 s. Beg also determined the Earth's axial tiltas degrees, which remains the most accurate measurement to date. References : Bragg, M On Giant’s Shoulders. J. Wiley & Sons, Inc. Pubs. U.K