Jung's book advances a sophisticated thesis to explain the genealogy of the essentialist image of Islam – a modern social imagination about Islam and Muslims. It observes similarities in the image of Islam found in the writings of Islamists and some Western scholars and asks, “Why do orientalists and Islamists similarly define Islam as an all-encompassing religious, political and social system?” (p. 7).

Underlying this image of Islam are certain assumptions: that Islam is a total way of life whose bedrock is a legalistic outlook; that it has a pure essence against which the observed forms can be checked for “aberrations”; and that this essence lies in Islam's origin. In the writings of the orientalists this Islam and the cultures shaped by it are sharply distinguished from the image of European cultures as dynamic, democratic and pluralistic, with religion being just one element of life. Though the essentialist image of Islam competes with what is called the constructivist image of Islam, social and political developments over several decades, the author tells us, have helped sustain its preponderance. Jung's aim is to challenge the predominance of the essentialist image by taking away its greatest appeal – its naturalness – by showing its contingency. Methodologically this is done by the genealogical analyses and application of the concept of “global public sphere” as an analytical device to understand the stage of the world society in which multiple modernities play out.

Jung situates the emergence of the modern essentialist image of Islam in the broader context of modernity. More specifically, he shows four overlapping and inter-penetrating processes at work over the last two centuries. First was the emergence of a modern image of universal religion based on liberal Protestantism and underpinned by a modern European cognitive episteme (the unifying paradigm of knowledge). This religion was private, located in individual faith, and unworldly. Its main architects were nineteenth-century theologians and Orientalists such as David Strauss and Robertson Smith. Second, Islam was postulated as the “Other” of modern European religion (and culture) by imagining it as collectivist, political and legalistic; as life, not just as a part of life. In the hands of Orientalists and the founding fathers of Islamic studies such as Goldziher, Snouck Hurgronje, Becker and Hartmann, Islam became “an ideal type of traditional religion” (p. 155) and a problem for modernity. Third, the early notables of Islamic modernism (across Muslim societies) began to share this image of Islam through their involvement in the global public sphere. Fourth, in the context of post-colonial power politics and facilitating technological modes, the essentialist image of Islam provided a fertile ground for the formation of Islamist revivalist discourse in the writings of people such as Sayyid Qutb and Mawdudi. The bulk of the book (chapters 4 to 6) is an empirical investigation into these processes through genealogical analyses of biographical sketches of selected social actors, showing the circulation of ideas in the global public sphere connecting theological studies to oriental studies to Islamic studies. In these fascinating chapters, Jung shows the role of teacher–pupil relationships, the influence of books, social events, correspondences, personal encounters and travels across Europe, West and South Asia.

Ignaz Goldziher (d. 1921) and Jamal al-Din al-Afghani (d. 1897) can serve as brief illustrations of interconnected biographical sketches that act as “nodal points” in Jung's analyses. Goldziher, one of the founders of Islamic studies in Europe, was a link between the European discourse on religion, state and science, and the founding thinkers of Islamic modernism. His letters, personal encounters and travel connected him on the one hand to Fleischer, Nöldeke, Renan and Robertson Smith and, on the other, to Sheikhs of Al-Azhar and reformists like Tahir al-Jazairi and al-Afghani. The peripatetic life of al-Afghani embodied the increasing interconnections between metropolitan cities of Europe and several parts of Muslim societies. In his thoughts, Islam served as an ideological rallying point, mediating his anti-colonial stance which in turn reverberates in the Islamist revivalist writings.

In these genealogical relations we see the “intellectual landscape that suggests the rise of a public sphere gradually expanding into a global dimension” (p. 99). For Jung, it was the participation in this sphere and the internalization of its cognitive and semantic structures, and not any ontological essentials of Islam, that evolved into the consensus among orientalists and Islamists. In this sense, the book brings out the impact of the “ontology of orientalism” on “the self-interpretation of Islamic culture” (p. 9), something that Jung believes the tradition of scholarship following Said's Orientalism fails to do.

The book raises some new questions and carries some unresolved tensions. I will mention two here. First, Jung seems to assume that the modern essentialist image of Islam is wholly a product of modernity. However, it can be argued that Islamic modernists imbibed an essentialist image of Islam not only because they were part of a global public sphere shaped by the European Orientalist imagery but also because it had some resonance within their own tradition. The historical self-image of Islam carries many strands that parallel a modern essentialist image. A fuller understanding of the modern essentialist image also requires an exploration of historical self-interpretations of Islam. Second, there remains a tension in the book between the thesis of global public sphere and the notion of multiple modernities. Conjoined though they may be, the European and Muslim public spheres were shaped by unequal power and force of discourse. In the end, the modern episteme remained European in its origin and Muslim actors were relatively late arrivals forced to “conform to a high degree” (p. 115) to the established discursive patterns. It is thus hard to see Muslim participants as producers of alternative modernity.

The book is particularly useful for those who have wondered why the popular (and sometimes academic) image of Islam in the West is so much at variance with the lived realities of Muslim societies; and why is there a similarity in the image of Islam found in the writings of Islamist and some Western scholars. To them, Dietrich Jung's book may provide a plausible and perhaps persuasive response.