In a curious and much-discussed passage in De insomniis, Aristotle claims that if a woman looks into a mirror during her menstrual period, her gaze will cause a blood-red stain to appear on the mirror’s surface. Modern commentators have struggled with the passage and its authenticity has been both questioned and defended. In the medieval Latin reception of Aristotle’s treatises on sleep and dreams, many of the commentators devote considerable attention to Aristotle’s account of the mirror phenomenon and try to harmonise it with his overall theory of perception as well as with his theory of motion. The paper analyses the development in a number of Latin commentaries on De insomniis from the twelfth and thirteenth centuries.

The trilogy Forms of Representation in the Aristotelian Tradition investigates how Aristotle and his ancient and medieval successors understood the relation between the external world and the human mind. It gives an equal footing to the three most influential linguistic traditions – Greek, Latin, and Arabic – and offers insightful interpretations of historical theories of perception, dreaming, and thinking. This final volume focuses on intellectual operations and analyses some of the most exciting issues pertaining to the conceptual representation of the external world. The contributions cover the historical traditions and their impact on contemporary philosophy of mind. 

The trilogy Forms of Representation in the Aristotelian Tradition investigates how Aristotle and his ancient and medieval successors understood the relation between the external world and the human mind. It gives an equal footing to the three most influential linguistic traditions – Greek, Latin, and Arabic – and offers insightful interpretations of historical theories of perception, dreaming, and thinking. This second volume focuses on dreaming and analyses some of the most prominent problems connected to dreams as representations. The contributions in this volume address the core Aristotelian texts and their reception, up to and including contemporary scientific discourse on dreaming. 

Aristotle’s De memoria et reminiscentia (‘On Memory and Recollection’) is the oldest surviving systematic study of the nature of human memory. Forming part of Aristotle’s other minor writings on psychology that were intended as a supplement to his De anima (‘On the Soul’) and known under the collective title Parva naturalia, Aristotle’s De memoria et reminiscentia gave rise to a vast number of commentaries in the Middle Ages. The present volume offers new knowledge on the ancient and medieval understanding of Aristotle’s theories on memory and recollection across the linguistic borders and philosophical traditions in the Byzantine Greek, Latin, and Arabic reception.

The articles in this issue are a selection of the papers presented at the conference Knowledge as Assimilation, held at the University of Helsinki on 9-11 June 2017. The conference was the result of a collaboration between two research groups that have been established in Finland and Sweden from 2013 onwards: the research project Rationality in Perception: Transformations of Mind and Cognition 1250-1550, funded by the European Research Council (2015-2020) and hosted by the University of Helsinki, and the research programme Representation and Reality: Historical and Contemporary Perspectives on the Aristotelian Tradition, funded by the Riksbankens jubileumsfond (2013-2019) and located at the University of Gothenburg.

The twelve essays in this volume all began their existence as contributions to workshops held between 2009 and 2011 by a Danish-Swedish research network called The Aristotelian Tradition: The reception of Aristotle’s works on logic and metaphysics in the Middle Ages, headquartered in Gothenburg and funded by the Bank of Sweden Tercentenary Foundation. Most of them were written by members of the network, some by invited speakers. The volume includes studies of texts by, among others, Apuleius, Boethius, Anonymus Aurelianensis III, Michael of Ephesus, Averroes, Anonymus Cantabrigiensis, Nicholas of Paris, Robert Kilwardby, Anonymus O, Thomas Aquinas, William of Ockham, and Francisco Suarez, relating to themes and passages in Aristotle’s Categories, On Interpretation, Prior Analytics 1, Posterior Analytics 1, Sophistical Refutations and Metaphysics A and Z. The book concludes with a new edition, with English translation and commentary, of the first part of a fiercely anti-Aristotelian work, which has been described as the starting-point for Renaissance Platonism and Aristotelianism alike: George Gemistos Plethon’s On Aristotle’s Departures from Plato.

In De somno et vigilia, Aristotle states that sleep is an incapacitation of the first sense organ that occurs when the capacity for sensation has been exceeded. In the same treatise, however, Aristotle also mentions the phenomenon of motion and other waking acts performed in sleep and claims that sense perception is a necessary condition for such acts to occur. When the medieval exegesis on the Parva naturalia evolved in the thirteenth century, how Aristotle’s remark on motion in sleep could be reconciled with his definition of sleep as an incapacitation of the senses became one of the most frequently discussed problems. This article analyzes the theories on this subject in the most influential commentaries on Aristotle’s treatises on sleep and dreaming in the thirteenth century.

The Roman statesman and philosopher Anicius Manlius Seuerinus Boethius (c. 480–c. 525) translated and wrote commentaries on most of Aristotle's logical works. In addition, he wrote several treatises on logic, including two monographs on the categorical syllogism, which are commonly known as De syllogismo categorico and Introductio ad syllogismos categoricos. The present study is the first critical edition of the former. De syllogismo categorico divides into two books of which the first is an account of the categorical proposition and the second deals with the categorical syllogism. The ultimate sources are Aristotle's Peri hermeneias and Analytica priora, but certain dispositional, terminological, and doctrinological features show that the text is heavily influenced by the tradition of the Greek commentators. From the rediscovery of Boethius' logical writings in the 10th century until the mid-12th century, Aristotle's doctrine of the categorical syllogism was known chiefly through Boethius’ De syllogismo categorico. The influence by as well as on the work is discussed in the introduction to the present study. The reconstitution of the text rests on collation of 44 manuscripts dating from the 10th to the 15th century. An analysis of the interrelation of the manuscripts leads to the conclusion that all extant manuscripts descend from a common archetype but that the tradition is severely contaminated and cannot be described by means of a stemma codicum. The text is primarily based on the fifteen earliest text witnesses, among which a formal hierarchy is established. The Latin text is presented with a critical apparatus, an apparatus fontium, a translation, and notes. Variant readings in the later manuscripts are reported in an appendix.