Bergson's key philosophical concept was "duration", encompassing both memory and life. This text analyses this central but complex concept through a close reading of one of Bergson's key works "Matter and Memory", setting it in the broader context of Bergson's other writings.

The Challenge of Bergsonism explores how Bergsonism questions our ways of thinking, particularly the concept of reality, and ultimately demands a return to ethics. The book also includes the first English translation of Jean Hyppolite's highly influential essay, "Various Aspects of Memory in Bergson".

"...a meticulous yet clear tour through the fundamental concepts of a philosophy that so far has not received the proper attention. Readers are able to come to grips with the meaning and relevance of Bergson's concepts of the image, memory, sense, and duration. Lawlor manages to simultaneously explain the theory and awaken interest in further study of a body of thought that offers a refreshing alternative to the dominant approaches to philosophy." -CHOICE, 5/04