This ambitious book by a young author (it is a lightly revised doctoral dissertation) tackles the most abstruse aspect of Marguerite Porete's Mirror of simple souls: its theology. Familiar hazards for the reader of Marguerite's refractory work lie in challenges concerning its format, structure, vocabulary and proclivity for paradox. And still there is another: since ‘the soul that writes this book’ is ‘annihilated’, does one's own soul need to be annihilated in order to reach its meaning? Nevertheless, Hahn-Jooss courageously forges ahead. Her strategy is original. Instead of pursuing the soul's ascent ‘vertically,’ she seeks to expose the ‘deep structure’ of the work ‘horizontally’ by moving topically. In four chapters she considers respectively: ethics; person (body/soul, ‘self,’ will); understanding; and ontology. ‘Horizontality’ also denotes her programmatic attention to the condition and practices of pre-annihilated souls, including souls that never will be annihilated, although ‘verticality’ does triumph in the chapter on ontology which concerns itself nearly exclusively with the being/non-being of the annihilated soul. Much to her credit, Hahn-Jooss strives for clarity by means of highly articulated organisation and frequent reiterations. On the other hand, her study is loaded with distancing quotation marks, technical theological terminology, and sesquipedalian neologisms (‘relationsontologisch’, ‘Enthierarchisierung’, ‘in-Beziehung-Sein’). It is impossible in a short review to summarise all the author's positions. Instead I will mention four that are prominent. Hahn-Jooss controversially proposes that for Marguerite the virtues are ‘fully valid messengers [vollgütige Botschafter] of perfection in God’, and, equally controversially, that for Marguerite the annihilated soul needs to maintain some relationship to the outside world and care for the neighbour. Thirdly, she contributes usefully to the discussion of recurrence and pre-existence by favouring the view that a Neoplatonic element is present in the Mirror – an outflow and return-flow of the soul from an ‘eternal One’ [Ur-Einen] – that is difficult to reconcile with the orthodox doctrines of creation and fall from sin. Lastly, she follows a general consensus, albeit with strong original argumentation, in maintaining that the Mirror teaches a maximum of proximity to God in this life but not the possibility of deification. This is an important book, highly recommended to all Marguerite specialists who can negotiate its German. Aside from Irene Leicht's book of 1999 (Marguerite Porete: eine fromme Intellektuelle und die Inquisition), I know of no work that considers the theology of the Mirror so thoroughly. Hahn-Jooss, moreover, can be counted upon to alert readers to passages and issues that previously have been little noticed. Yet I do have criticisms. I refer first to bibliographical negligence. Most crucially the author missed Geneviève Hasenohr's announcement (published in 1999) of a hitherto unnoticed fragment of the Mirror in the original Picard dialect, and she missed Luisa Muraro's proof (published in 1996) that the title commonly accorded to Marguerite's book is incorrect. Calling attention to these absences is not empty point-scoring. Rather Hasenohr's discussion of the new fragment highlights the insufficiencies of the Chantilly text on which Hahn-Jooss relies. (I have attempted in a recent publication to demonstrate that Hasenohr's discovery nets still greater returns.) As for Muraro's finding that the title does not refer to souls ‘who only dwell in the will and desire for love’ (an excrescence lodged only in the Chantilly text), this helps to cut the ground from any programmatic concern with the state of pre-annihilated souls. Even aside from that, the author's ‘horizontal’ strategy of studying ‘before’ and ‘after’ seems considerably misguided. After all, Marguerite is interested in the early stages of the soul's progress only in order to emphasise how they will be transcended, and to tax those who are caught up in them. Thus, while it is original and not entirely uninteresting to note differences between the two kinds of souls that are never annihilated (perilz and marriz), the results seem largely beside the point. Much more problematic are methodological false steps. In looking for evidence to support her thesis of a positive role for the virtues, Hahn-Jooss (p. 72) quotes ‘Reason's’ pronouncement that ‘without these virtues no one can ... come to perfection of life [and] with them no one can be deceived.’ But to imply that ‘Reason’ speaks for Marguerite disregards repeated admonitions that ‘Reason’ is an ass who takes the straw and leaves the grain. At another point (pp. 78-9) Hahn-Jooss omits words from a quotation to serve her purpose: rather than offering St Paul as a model, Marguerite writes that ‘wishing for nothing in God … bears no comparison … not even’ with the rapt Apostle. Similarly (p. 96) she truncates a quotation: the Soul ‘in such exalted rest could help her neighbors, but the thoughts of such Souls are so divine that they do not dwell upon passing or created things’. Throughout Hahn-Jooss ignores variant readings in the Middle English Mirror that result in doctrinal positions different from those that she accepts from the Middle French and Latin. Even though she includes Colledge and Guarnieri's pursuit of this crucial matter in her bibliography, she nowhere stops to consider their proposition that ‘[perhaps] the English best represents what Margaret first wrote’.