Memo in the science of principles

This is a memo in the science of Usul al-Fiqh, which I prepared according to the curriculum prescribed for third-year students of the College of Arabic Language at Al-Azhar. And I saw it appropriate to present before it a brief word about the history of that great science, its importance, and its esteemed value, which distinguished scholars have cared for from the dawn of Islam until now, and have authored numerous works with abundant material and great benefit; so that the student may understand the value of that science, and realize that what is mentioned in that memo is only a small part of the vastness, a drop in the ocean, of what the prescribed curriculum and the allotted time for its study include. And I ask Allah to benefit from it, to make it purely for His noble face, and to grant us success and guidance in all we do. Indeed, He is the Hearing of supplication, the best disposer of affairs.