The reason for presenting the views in the form of theories is to offer content that can be followed by general readers as well as experts. In this context, the target audience of the book consists of all readers, whether they are experts in any field of the history of thought or not. The work titled Metaphysics, published in three volumes as the first step of the "Theories in Islamic Thought" project, which Prof. Dr. Ömer Türker has put forth with diligence and effort spanning many years, is a monumental step that will create the possibility of establishing a common language and making a collective intellectual move when considered together with the other upcoming books in the series.