By using sources such as Mizan ül-Hak, Düstur ül-Amel, Tarih-i Kostantiniyye ve Kayasıre and Tarih-i Frengi Tercümesi, this book analyzes Kâtip Çelebi, one of the most prominent intellectuals of the 17th century. Kâtip Çelebi, who might be seen as a renaissance man, was an influential thinker who contributed to a variety of different fields including history, politics, naval warfare, society, philosophy, Islamic law, and many others. This book aims to explore Kâtip Çelebi’s thoughts on 17th century crises, including his ideas on how to reform the Ottoman state structure. It discusses his ideas on society and authority which are grounded in reason and religious law simultaneously. This work suggests Kâtip Çelebi provided an authentic intellectual perspective that was critical of different sides in the above-mentioned debates and provided a moderate and balanced approach when analyzing various issues.