This chapter turns to consider John of La Rochelle’s earliest work on the soul, his Tractatus, which does not treat the six questions covered in the Summa de anima but focuses exclusively on the powers of the soul themselves, both cognitive and volitional, and their operations. The chapter addresses the contention of the Tractatus’ editor that this work is merely a preparatory study for the more mature Summa de anima, showing how it outlines a unique psychology, heavily influenced by the Islamic philosopher Avicenna, which John incorporates into the Christian tradition through identifying rough points of contact in the work of John of Damascus and pseudo-Augustine.

This chapter illustrates how the psychology of the Tractatus is incorporated into the Summa de anima and builds on the exposition of the Tractatus provided in Chapter 5 with a view to explaining how precisely John of La Rochelle conceived the operation of the senses and the human mind. The chapter argues that John used Avicenna to endorse an ‘active’ theory of cognition in which innate categories of the mind, later known as transcendentals, play a role in shaping human understanding of the senses, which nonetheless provide crucial material to be rendered intelligible.

This chapter focuses on the doctrine of free will itself, which is one area in which the Summa Halensis draws more on Alexander of Hales than on John of La Rochelle. The two main areas in which it does so concern the questions of whether free will consists more in the will or in reason, and whether it can only will the good. On both these topics, the Summa Halensis departs from the past tradition represented most famously by Augustine in affirming that free will consists more in will than in reason and that it is capable of willing both good and evil.

This chapter considers the early Franciscan response to three further questions about the powers of the soul which arose from the early scholastic reading of Arabic philosophical sources particularly. These inquire whether the soul consists of one or three powers (vegetative, sensitive, and rational), whether the soul is identical with its powers, and whether the vegetative and sense powers survive the death of the body. As in Chapter 3, the Franciscan response to these questions is situated in relation to those provided by other early scholastic theologians.

This chapter provides a brief account of the most significant theologians who worked at the university of Paris during the early thirteenth century, mentioning their unique contributions to the development of their discipline and the extent to which they engaged with the new philosophical materials to answer questions related to human nature.

This chapter discusses the important developments in the philosophy of the soul that took place between around 1150 and 1215, which played a role in early Franciscan thought on human nature. These include the introduction of medical sources translated from Greek and Arabic into Latin, and, above all, the translation of Greek and Arabic philosophical works in the latter half of the twelfth century. The chapter explores the factors which mitigated the reception of those sources in the early thirteenth century and the reasons why their appropriation is particularly extensive in the work of John of La Rochelle.

Aquinas refers to that in virtue of which the patient is acted upon as passive potentiality; and he claims that to every type of active power, there corresponds a determinate type of passive power. This chapter considers Aquinas’s views on passive powers. The chapter first considers Aquinas’s views on the constituents of material substances that give rise to their passive potentialities for being acted upon. Aquinas holds that material substances have passive potentialities in virtue of both their matter and their qualitative forms. The chapter next considers Aquinas’s views on how a material substance’s passive potentialities are identified and distinguished from one another. Finally, the chapter argues that Aquinas thinks that a substance’s passive potentialities for undergoing action are the same as its potentialities for existing in determinate ways. For example, a pot of water’s potentiality for being heated is the same as its potentiality for being hot.

On Aquinas’s view, a human being is a material object, a hylomorphic compound of prime matter and the substantial form of a human being. That form is capable of existing on its own, apart from matter; and it does so in the period between the death of a human being and the resurrection of his body, when that form configures matter again. The resurrection of the body is not a reassembly of bodily bits that had previously composed the body; it is more nearly a reconstitution of the substantial form with prime matter. Finally, after death some human beings go to heaven. In heaven, a human being is perfected, so that the true nature of a human being is revealed best in the condition of human beings in heaven. A human being in heaven sees God and is united in loving relationship with God and with all others who are also united to God. In this vision and union, she has the full perfection of her human nature and also her complete beatitude.

We recognize one of a pair of opposites by means of the other, Aquinas says. Just as we understand what darkness is only by reference to the notion of light, we must understand what evil is by reference to the notion of good. What is good is what is desirable. Every nature desires its own being and perfection, so we can conclude that “the being and perfection of every nature has the character of goodness.”1 Evil, then, cannot be a being or nature; it must be an absence of good. Not every absence of good counts as evil, however. A stone lacks the power to see, but its “blindness” is not evil: The nature of a stone has no aptitude for sight, and so it is no part of the perfection of a stone that it should see. Thus, evil is not a simple negation of good, but a privation of good; and we recognize a privation by comparing it with the fullness of being that is characteristic of a thing’s nature.2 Evil is a defectus: a falling short of, or falling away from, what is good.

Aquinas thinks that natural efficient causes can act through the active powers of substances distinct from themselves. Aquinas identifies two different ways in which an efficient cause can operate through another cause’s power, namely as an instrumental cause or as a secondary cause. The chapter discusses Aquinas’s basic understanding of instrumental causality and secondary causality. Instrumental causes are employed by another cause, called a principal cause, to reach its end. In acting for a higher end, the instrument acts through the principal cause’s power. Secondary causes are like instruments insofar as they cannot act unless a higher cause exercises its power. However, secondary causes differ from instruments insofar as they act for their own ends. The chapter discusses Aquinas’s examples of instrumental and secondary causality in the natural world. Aquinas uses the notion of instrumental causality to understand how higher-level natural powers, such as the nutritive power, employ the actions of elemental powers, such as heat, to reach their ends. He regards terrestrial causes as secondary causes that act through the power of the heavenly bodies.