This book examines and analyses the legitimacy of the widely held claim that Mulla Sadra's philosophy (al-hikmah al-muta'aliyyah) is a synthesis of principles and doctrines drawn from revelation (wahy), gnosis ('irfan/ma'rifah) and discursive philosophy (al-hikmah al-bahthiyyah). In Mulla Sadra's view, these three major sources of knowledge can be brought together without contradiction and accorded their respective roles in the human quest for true and certain knowledge. This book discusses and demonstrates how Mulla Sadra achieves this synthesis as contained in and exemplified by his text, al-Hikmah al-'arshiyyah or Wisdom from the Divine Throne. An evaluation on whether or not Mulla Sadra's synthesis is successful is also undertaken. The criteria used for the evaluation are the internal coherence of his ideas, their conformity to Islamic teachings and impact on Islamic thinkers after him.