This study is based on two methodologies: Historical Methodology: To highlight the life of the author, his birth, his death, his masters, his students and his writings. Investigation methodology: The approach adopted in academic universities. It is adopted in this thesis to highlight the manuscripts of the book, and the manuscripts study and investigation. Contents: This thesis is composed of an introduction, two chapters and a conclusion as follows: Introduction: presents the importance of morphology, previous studies, reasons for choosing the subject, methodology of the study, and contents of the thesis. First Chapter: Titled (Study) This chapter includes two titles and eleven subtitles as follows: First Title: Introducing the Author in five subtitles as follows: First Subtitle: Name and Ancestors Second Subtitle: Birth and Death Third Subtitle: Scientific Life Fourth Subtitle: Masters and Students Fifth Subtitle: Scientific Endeavors Second Title: Introducing the Manuscript in six subtitles as follows: First Subtitle: Book Title and Reason for Composition Second Subtitle: Attributing the Book to Al-Khalili and Description of Manuscripts Third Subtitle: Author's Methodology Fourth Subtitle: Between Simplification and Maqaleed. Fifth Subtitle: Reference and Figures Sixth Subtitle: Evidences Second Chapter: Titled (Investigation) Finally, the conclusion including the most significant findings of research is presented. Then, the indices followed all the above. Findings: I would like to list and summarize a group of some findings and notes that have come out of my study of this subject matter below. 1) Sheikh Al-Kahlili followed a methodology concise and exclusive to the most important requirement. He stated this methodology several times in the book explicitly. 2) Sheikh Al-Khalili indicated the most evident opinion in an issue. 3) Sheikh Al-Khalili methodology is mostly characterized by conversation and discussion as he invented the existence of a student to converse and discuss. This method assists the student to correctly consolidate and understand information. 4) Frequently, Sheikh Al-Khalili issued the section under consideration with a regulation or measurable rule, then he referred the immeasurable to his book "Maqaleed" and he mentioned them sometimes. 5) Sheikh Al-Khalili explained terms that needed clarification or illustration. This method is frequent in his book. In addition to this impressive educational method, the explanation of meanings of words relieves burden incurred by students to search for these meanings. 6) Simplification Book is a complement to what the author missed in his book "Maqaleed". This is evidently clear in "Simplification", particularly in the introduction and conclusion. 7) Sheikh Al-Khalili concentrated on extensive language and did not say that those who adopted measurement were mistaken. Thus, he disagreed with the popular opinion. 8) Sheikh Al-Khalili used the term "Object" likely as used by his master Naser Ibn Abi Nabhan. 9) Sheikh Al-Khalili pursued the weigh method. At times, he agreed and disagreed with the majority, which signifies following a weighed method not a traditional method.