In Chapter 3, I argued that Dante’s Purgatory represents figuratively the moral journey of Christian penance to heaven (the beatitudo vitae aeternae), in opposition to a predominant ‘secular’ reading in twentieth- and twenty-first-century scholarship. Even scholars who have interpreted the ethics of Purgatory as distinctively Christian, however, have typically turned to Aquinas’s Summa Theologiae to gloss Dante’s approach to the seven capital vices. In this chapter, I show that the moral theology of Dante’s Purgatory is, instead, drawn from Peraldus’s widely diffused and extremely influential treatise De vitiis. This is highly significant for understanding Dante’s poem, because Aquinas and Peraldus adopted very different approaches in their treatment of the vices and virtues. In the first part of the chapter, I set out the pastoral exigency to reform, and provide a new rationale for, the ethical scheme of the seven capital vices. In the second and third parts, I provide a comparative critique of Peraldus’s and Aquinas’s approaches to this reform. In this way, I am able to highlight the characteristics – including the weaknesses – of Dante’s poetic treatment (which clearly follows Peraldus’s treatise). The parallel in ethical content between Peraldus and Dante is matched, furthermore, by a parallel in form: Peraldus’s De vitiis invites us to imagine Dante assuming, in Purgatory, the role of a vernacular preacher against vice, with the reader envisaged as a Christian sinner.

Organising the Seven Capital Vices

The tradition of the deadly sins or capital vices takes its Christian origin from the desert fathers. For Evagrius Ponticus, the eight ‘evil thoughts’ reflect the full arsenal of the devil through which he attempts to attack the monk in the desert.Footnote ¹ The earliest form of organising the vices seems to have been as a causal series. This model was introduced to the West by John Cassian, for whom the vices ‘are linked among themselves by a certain kinship and, so to speak, concatenation’ (Collationes, v. 10).Footnote ² Like Ponticus, Cassian orders the vices from the carnal to the spiritual: first gluttony, which leads to lust; from lust comes avarice; from avarice wrath: from wrath sadness; and from sadness sloth. The monk’s moral development may itself lead to the final, most severe vices of vainglory and pride: in other words, after overcoming each of the six vices, the monk is tempted to set himself up above others.Footnote ³

Ultimately, however, it was the order established by Gregory the Great which would become standard in the Latin West. Like the desert fathers, Gregory underlined the causal connection between the seven capital vices. Unlike them, Gregory gave priority to the spiritual over the carnal vices; he added envy to the list, conflating, in the process, tristitia (sadness) and acedia (sloth); and he made pride the root of all. So, for Gregory, the first vice, vainglory, begets envy because in seeking an empty renown, the soul feels envy towards one able to obtain it; the last vice, lust, is caused by gluttony, as the inordinate consumption of food disposes the soul to sexual wantonness.Footnote ⁴ Allied to his reforming zeal and concern with evangelisation, Gregory’s authoritative ordering of a system of Christian ethics around the seven capital vices had an enormous influence on the medieval Church. Thus, for example, Peter Lombard’s Sentences – the theological textbook for the later twelfth and thirteenth centuries – simply states that ‘it is well known that there are seven capital or principal vices, as Gregory says on Exodus, namely vainglory, anger, envy, sloth or sadness, avarice, gluttony, lust’.Footnote ⁵ The whole moral abyss of sin is then pegged onto this skeleton structure: ‘From these, as if from seven springs, all the deadly corruptions of souls emanate. And these are called capital because from them arise all evils.’Footnote ⁶

Nonetheless, obvious theoretical problems arose with the system of the seven vices. Notably, it was difficult to find seven virtues to oppose them. A standard medieval grouping of the virtues into the cardinal (prudence, justice, temperance, and fortitude) and the theological (faith, hope, and charity) does not provide a meaningful parallel with the seven vices. Likewise, the proposed lists of seven remedial virtues ran into conceptual difficulties.Footnote ⁷ Moreover, the list seemed to exclude such primary and pressing vices as faithlessness and heresy.Footnote ⁸ Theologians experimented, therefore, with alternative systems of classification, each of which had distinct advantages over the list of seven vices.Footnote ⁹ The sins of thought, word, and deed conveniently parallel the three stages of confession: compunction (of heart), confession (of mouth), and satisfaction (through actions). The three concupiscences (of the flesh, the eyes, and the pride of life) have strict biblical foundation (I John 2:16) and map onto the desires of the body, the desire for external goods, and the mind’s desire to raise itself above others. In addition, the decalogue gives a more comprehensive account of the moral law in its positive dimension.

Why, then, did these alternative models not displace the system of the seven vices? Why, instead, were they actually incorporated into and assimilated by it? The reason is not theoretical clarity, but rather pastoral effectiveness. The system of the vices was, quite simply, more popular and more memorable. The Fourth Lateran Council (1215) formally impelled all Christians to confess their sins to a priest at least once a year; the scheme of the seven vices gave each individual layman a simple, but potentially rich structure to his or her moral life. Indeed, preaching on the seven capital vices became ‘commonplace in sermons following the Fourth Lateran Council’. Medieval theologians did not, in other words, start from the drawing board. Whether they liked it or not, the ethical model of the seven capital vices was ingrained in the practices and cultural imagination of medieval laypersons.

Thus, the theoretical exigency moved from replacing the system altogether to reforming it from within. One key area for development was in the organisation of the vices: there were clear limitations in a simply causal account (with one vice leading to another in a linear series). Theologians therefore adopted new rationales for the vices based on human psychology and even on cosmology or symbolism.Footnote ¹⁰ It is within this wider context that we may productively compare the approaches of Peraldus and Aquinas.

Peraldus and the Augustinian Theory of Disordered Love

Of the two Dominicans William Peraldus (c. 1200–71) and Thomas Aquinas (1225–74), Peraldus is now barely known, whereas Aquinas, canonised and a doctor of the Church, is one of the most persistent influences on Catholic philosophy and theology. During their lives, however, it was a different story. A decree required that every Dominican convent hold a copy of Peraldus’s Summa de vitiis et virtutibus in its library, and this work – as the number of extant manuscripts testifies – was widely diffused across the whole of Christian Europe.Footnote ¹¹ Dominican friars were expected to know Peraldus’s Summa ‘inside out’ and to be able to recite, on demand, any chapter or title from the work.Footnote ¹² The second part of Aquinas’s Summa Theologiae would only supersede Peraldus’s treatise as the Dominican handbook for moral theology and pastoral care in the late fourteenth century.Footnote ¹³ Given the authoritative status of Peraldus’s Summa even beyond Dominican circles, we can be confident that Aquinas knew it well. It is also plausible, as Leonard Boyle suggests, that Aquinas presents the second part of his Summa as, specifically, an improvement on and even a corrective to Peraldus’s Summa de vitiis et virtutibus.Footnote ¹⁴

William Peraldus – a prior of the Dominican Order in Lyon – composed his treatise on the vices (De vitiis) around 1236; his treatise on the virtues appeared early in 1249.Footnote ¹⁵ From the mid-thirteenth century, the two treatises began to circulate together. Peraldus’s De vitiis is perhaps best described as an anthology of resources on each of the seven vices to be used by Dominicans in preaching and confessing.Footnote ¹⁶ It is a treasure trove of quotations from Scripture, the Church authorities (especially the Latin fathers) and the classics (with a preference for the moralists Cicero and Seneca). It contains lists of exempla (principally from the New and Old Testaments) with pithy accounts of their lives and the moral lesson drawn, as well as memorable similes, images, and extended metaphors (for example, with regard to the mountain of pride).Footnote ¹⁷ In the longer and more comprehensive chapters, detailed manifestations of each vice are treated as well as aspects of a vice which are specific to a given sector of society. For example, a section is devoted to the evil of cloistered religious (‘claustrales’) taking pride in magnificent buildings: as they are dead to the world, a sepulchre is more fitting for them than a palace.Footnote ¹⁸

A brilliant anthology of resources for use in preaching and confessing, Peraldus’s De vitiis is not a tightly organised account of the vices to be read in sequential order: in the treatise, structure is subordinated to practical utility. After a short section on vice in general, Peraldus treats gluttony and lust. He moves on to a major tome on avarice not for a formal reason, but, more crudely, because of utility: ‘After the vices of gluttony and lust, we shall speak of avarice because a treatise on this vice is more useful to preaching than a treatise on any of the other vices.’Footnote ¹⁹ Chapters on sloth, pride, envy, and wrath follow, and Peraldus concludes with a separate part on the sins of the tongue. Despite the unconventional order of his treatise, Peraldus does nonetheless open his fifth chapter on pride – the root sin – with a rationale for the seven capital vices as a whole. And it is this which interests us here.

Peraldus starts from Augustine’s understanding of virtue as ordered love and of vice as disordered love: ‘Sicut virtus secundum Augustin[um] amor est ordinatus: sic vitium est amor inordinatus.’Footnote ²⁰ This locus classicus comes shortly after Augustine’s depiction of the two cities in De civitate Dei: ‘Two cities, then, have been created by two loves: that is, the earthly city by love of self extending even to contempt of God, and the heavenly city by love of God extending to contempt of self.’Footnote ²¹ Virtue is rightly ordered love; rightly ordered love is love of the Creator.Footnote ²² A more precise taxonomy of love of God and its disorder is found in Augustine’s De doctrina Christiana. Misdirected love, he writes, has four species: first, to love what is not desirable; second, not to love what is desirable; third, to love some lesser thing too much; and fourth, to love two things the same where one is more or less desirable.Footnote ²³ Peraldus simplifies Augustine’s schema and divides disordered love into two main categories: love of an evil (amor mali), which may correspond to Augustine’s first category, and perverted love of a good through excess or deficiency (nimius vel nimis parvus) which, when expanded, conflates Augustine’s second, third, and fourth categories.Footnote ²⁴

Considering first the disordered love through excess or deficiency, Peraldus distinguishes two kinds of good: lesser goods (temporal and corporeal) and great goods (grace and meritorious works).Footnote ²⁵ The excessive love of lesser goods is the root of gluttony, lust, and avarice.Footnote ²⁶ The deficient love of great goods is the root of sloth.Footnote ²⁷ Peraldus’s attempt to explain the three further vices – pride, envy, and anger – in terms of the genus ‘love of evil’ (amor mali) is less straightforward. Augustine, nonetheless, had once again shown the way. The sinner, Augustine notes, desires self-aggrandisement: to set himself up above his fellow men. Such self-love, Augustine affirms, is better called hate because we fail, in this way, to love appropriately our neighbour who is, by nature, on a level with us.Footnote ²⁸ As the desire to be exalted implies the humiliation of one’s neighbour, pride is, albeit indirectly, the love of someone else’s evil.Footnote ²⁹ Nevertheless, Peraldus acknowledges that – properly speaking – hatred of neighbour is found in its pure form only in the vices of anger and envy.Footnote ³⁰ With anger, the cause of hatred is external (in another); with envy, the origin of hatred is internal (the self). He who is angry hates another and desires retribution because of an evil suffered. Thus, Peraldus defines anger as the desire for revenge (‘appetitus vindictae’).Footnote ³¹ The hatred consequent upon envy, by contrast, has its evil in the self (‘a propria malitia’). The recognition of another’s excellence leads neither to praise nor to emulation, but rather to sadness and the purely negative desire that evil should happen to one’s neighbour so that his or her excellence is diminished.Footnote ³²

Peraldus’s account of gluttony, lust, avarice, and sloth in terms of disordered love through excess or deficiency does fit naturally, I would suggest, within the wider Augustinian framework of a distorted relationship between man, the goods of creation, and the Creator. As Augustine puts it, the lower goods of this world must be used on our journey to the heavenly kingdom; if our desire for them is disordered, we get left behind and may even turn back altogether from the pursuit of our true happiness.Footnote ³³ In addition, this rationale gives a sense to what, at first, might seem the haphazard organisation of Peraldus’s treatise as a whole. Peraldus begins with the three vices which involve an excessive desire for created things: gluttony, lust, and avarice. He then moves to the vice of sloth which involves an insufficient love of the Creator, the greatest good.

Peraldus’s attempt to fit the vices of pride, envy, and anger into an overarching Augustinian scheme of ordered and disordered love is, however, less convincing. Pride has only an indirect relation to the general category: love of a neighbour’s evil. After all, the debasement of a neighbour is a potential consequence of – rather than the primary motive for – disordered self-love. With regard to anger, Peraldus’s definition fails to distinguish adequately between, on the one hand, the righteous indignation at a wrong suffered with the desire for just retribution and, on the other, an unbounded hatred of a person irrespective of the limits of justice. Furthermore, Peraldus’s definition of the quiddity of envy – as motivated by the desire to bring down a person to one’s own level – seems overly reductionist.

Peraldus’s rationale takes up only a very small part of his treatise. As we have seen, the work’s primary purpose is pastoral: to provide his Dominican confrères with an anthology of resources for preaching and confessing the seven capital sins. Nonetheless, the inadequacy of the Augustinian theory of disordered love to provide a convincing psychological framework for all seven vices left an obvious area of improvement for a successor in his order.

Aquinas’s Positive Moral Psychology for the Seven Vices

Aquinas’s contrasting approach to the vices in De malo is already apparent from his introductory etymology of the term ‘capital vice’. What makes a vice capital, for Aquinas, is that it has an end chiefly desirable as such, so that other sins are subordinated to it. For example, an avaricious person may commit the sin of fraud in order to acquire money.Footnote ³⁴ Where the starting point of Peraldus’s rationale for the capital vices is disordered love, Aquinas differentiates each capital sin with regard to good objects which may be desired or avoided. There are, he argues, three kinds of good objects which are desired: goods of the soul, goods of the body, and goods consisting in external things.Footnote ³⁵ The sin of pride aims at the goods of the soul: the excellences of honour and glory. The sins of gluttony and lust aim at the goods of the body: the preservation of the individual (through nutrition) and of the species (through sexual intercourse). The sin of avarice pertains to the goods consisting in external things. By contrast, the three remaining capital vices – sloth, envy, and anger – concern goods which are avoided because they present some kind of obstacle to another good inordinately desired. The sin of sloth (acedia) is an aversion to the good in itself (God) because, in seeking God, the soul is impeded in its desire for physical tranquillity or bodily pleasure. The sin of envy is an aversion to the good of another insofar as it diminishes one’s own excellence.Footnote ³⁶ Finally, the sin of anger comprises a resistance to the good of justice because it prevents the inordinate vengeance desired.

Let us now consider the advantages of Aquinas’s framework with regard to two vices – gluttony and lust – which naturally fit into Peraldus’s Augustinian schema and with regard to two vices – pride and anger – which proved for Peraldus especially problematic. Peraldus classifies gluttony and lust in terms of the excessive desire for the secondary good of pleasure. Aquinas, by contrast, reframes the two vices in terms of virtuous desires for goods of the body. For Peraldus, gluttony and lust are differentiated by their primary sense (taste and touch); for Aquinas, they are differentiated in relation to the purposes of each desire: preserving the individual through nutrition and preserving the species through sexual intercourse. Aquinas’s approach creates room for insufficient desire for food and drink (as in the case where someone desires to consume too little) and insufficient desire for sexual intercourse (Aquinas’s example is a husband who abstains from sexual intercourse, thereby failing to fulfil his marital duty). For Aquinas, it is the respective purposes of the goods of the body which set the rule for temperance, the virtuous mean. Food is necessary for the nutritive power of the vegetative soul; pleasure in its consumption is, therefore, natural. Gluttony resides, instead, in the sense appetite – it is, more precisely, the immoderate sensual desire to consume food. The generation and education of offspring is the purpose of the sexual organs; pleasure in sexual acts ordered to this end is, therefore, natural and good. Lust concerns any sexual act which is not properly related to the begetting of offspring. In addition, as the effective education of offspring requires the mutual cooperation of parents, Aquinas argues that every sexual union outside the law of marriage is also lustful.Footnote ³⁷ For Peraldus, then, the sins of gluttony and lust are related directly to an excessive desire for pleasure. In contrast, for Aquinas, these sins are related to the disorder which occurs when the good is not related to its proper end or ends. One further advantage of measuring the desire not by quantity, as in Peraldus, but by right reason is that this approach enables Aquinas to relate more effectively the acquired virtue of temperance to its infused counterpart, the natural to the Divine law. Thus, for example, Aquinas clarifies that virginity or celibacy is not contrary to sexual desire as an extreme. Although, before Christ’s coming, human and Divine law prohibited abstinence in order to multiply the human race, in the period of grace in which Christians are obliged to pursue spiritual growth, the celibate life is more perfect.Footnote ³⁸

Let us now turn to the vices of pride and anger, which Peraldus struggles to fit convincingly into his adaption of the Augustinian schema of disordered love. Peraldus locates pride negatively within the genus of hatred of one’s neighbour (alongside envy and anger). Aquinas, by contrast, reconfigures pride in relation to the excellences of honour and glory, reflecting his broader insight that every sin is based on a natural appetite for some good. In pursuing excellence, Aquinas affirms, a person seeks likeness to God’s goodness: the natural desire for excellence is, therefore, a good as not only humans but all created beings seek their own perfection. This positive reframing has four distinct advantages. First, Aquinas contextualises pride (as excess) and pusillanimity (as deficiency) in relation to the virtuous mean of magnanimity (the pursuit of excellence in accordance with reason and God’s command). Second, he links the vice of pride to the faculties of the human soul: the intemperate desire for excellence derives from the irascible appetite; the prior judgement that such excellence is one’s due derives from the rational will.Footnote ³⁹ Third, Aquinas allows for three principal species of pride: to desire an excellence beyond one’s measure (presumption); to attribute an excellence attained to one’s own merits or to God but given because of one’s merits; and to seek to hold an excellence exclusively even where the excellence is a kind to be shared by others or by all.Footnote ⁴⁰ Finally, Aquinas’s broad definition creates a natural connection between pride, as the excessive desire for excellence, and the vice of vainglory, as the excessive desire to manifest one’s excellence.Footnote ⁴¹ By contrast, Peraldus’s account of pride lacks a positive moral teleology and a convincing anthropology; its definition – ‘setting oneself up and debasing others’– is extremely narrow, corresponding, if at all, only to the third species outlined by Aquinas; and its classification in terms of ‘hatred of neighbour’ is very remote indeed from ‘glorying in one’s own merits’, a primary characteristic, for Aquinas, of vainglory.Footnote ⁴²

A major problem with Peraldus’s account of anger – as, simply, the desire for revenge – is that it leaves little space for a potentially positive emotion. In his own treatment, Aquinas takes – as his starting point – a debate amongst the ancient schools of philosophy about whether there might be a positive kind of anger. The stoics had argued that all anger is evil; the peripatetics, that some anger is good.Footnote ⁴³ For Aquinas, the stoics failed to distinguish the two kinds of appetite – of the rational will and of the sense appetite – pertinent to anger. Considering only the latter, the stoics classified anger as an evil, reasoning that all emotions, of the sense appetite, upset the order of reason. The peripatetics, by contrast, showed that even the sense emotion of anger may be a good. Although the spontaneous emotion of anger arising from an injury always clouds our judgement to some extent, anger – both of the sense appetite and of the rational will – may also follow upon our judgement; as such, it is an ‘instrument of virtue’ which helps the person to execute justice more readily.

Where Peraldus fails to disentangle the ambivalent emotion of anger (simply characterising it as a vice), Aquinas distinguishes the good and evil aspects of anger in relation to its end with two further terms: zeal is the emotion of anger righteously ordered to justice, while wrath signifies the inordinate desire for vengeance. In this way, Aquinas also sets out a vice of deficiency – an inordinate lack of anger – which, he argues, is equally destructive: it leads to negligence and invites men, whether virtuous or not, to evil by creating a context in which no retribution is carried out.Footnote ⁴⁴

Thus, in De malo, Aquinas frames his discussion of each of the capital sins in terms of a positive moral psychology: the vices reflect disorder in the proper functioning of man’s natural faculties and are related to good objects which may be desired or avoided. Aquinas also demonstrates that the four vices of desire – pride, avarice, gluttony, and lust – undermine with a false substitute the three conditions of happiness: that which makes us truly happy must be a ‘complete good’, it must be ‘intrinsically sufficient’, and it must be ‘accompanied by pleasure’. Excellence, the goal of pride, appears so desirable because a good is complete insofar as it has an excellence. Riches, the goal of avarice, especially promise sufficiency of temporal goods. Food and sexual intercourse, the goals of gluttony and lust, give the greatest sensual pleasure. In this way, the four vices of desire present objects which apparently share the conditions of happiness, and their appearance draws man, who naturally seeks his happiness, to them. In a parallel way, the vices of avoidance – sloth, envy, and anger – are characterised by displacement of the true good because of a disordered desire for some lesser good: thus, with sloth, physical tranquillity is preferred to the true peace of the soul in God; with envy, one’s own excellence is preferred to the truthful acknowledgement of others’ gifts and works; and with anger, vengeance is preferred to the execution of justice.

Aquinas also offers a deft solution to the problem, posed emphatically in Peter Lombard’s Sentences, of the apparent dual priority of pride and avarice as chief sins. While showing how pride and avarice – in both their general and their specific senses – may be understood as the root of the other vices, he nonetheless reaffirms the priority of pride which Gregory established by integrating the authority of Augustine: he opposes pride, as the ‘root and queen of all sins’, with charity, as the queen of the virtues.Footnote ⁴⁵ Aquinas thereby re-incorporates the Augustinian framework of the two cities but mitigates Peraldus’s problematic approach with its binary opposition between love of an evil and disordered love of a good.

There are major differences, therefore, between Aquinas’s treatment of the vices in De malo and Peraldus’s treatment in De vitiis. There is, however, little difference in substance between Aquinas’s account of the vices in De malo and his account in the Summa.Footnote ⁴⁶ Although Aquinas treats the vices in traditional causal order in De malo (with a chapter devoted to each in turn), Aquinas’s rationale does not. That is, in discussing the moral framework of the vices, Aquinas considers first pride, gluttony, lust, and avarice (as vices of desire), and then sloth, envy, and anger (as vices of avoidance).Footnote ⁴⁷ Equally in De malo as in the Summa, Aquinas adopts principles based upon human psychology and moral teleology, having already moved away from the organising principle of concatenation. Moreover, Aquinas not only explicitly affirms that it is correct to speak of seven capital vices in the Summa, but also provides a precise summary of the same rationale to be found in his treatise De malo.Footnote ⁴⁸ The only very slight difference is that, in the second category of avoidance, Aquinas’s subdividing principle in the Summa is no longer (as in De malo) between avoidance of a good (sloth and envy) and resistance to an evil (anger); rather, it is between avoidance of our absolute good (sloth) and avoidance of the good of another (envy and anger).Footnote ⁴⁹ Thus, in De malo, Aquinas distinguishes sloth and envy with respect to the object avoided (avoidance of the chief good or of the good in another); in contrast, in the Summa, he distinguishes envy and anger with respect to the mode of avoidance (sadness or resistance respectively).Footnote ⁵⁰ Aside from this one minor nuance, the rationale for the vices in the Summa is entirely consistent with that given in De malo.

In both De malo and the Summa Theologiae, Aquinas affirms the positive mode of desire and avoidance which underlies a capital vice or its offspring. What is strikingly different, of course, is that in the Secunda secundae, the vices are incorporated into an ambitious and original synthesis as deviations from the true path of the virtues. Aquinas’s first reason for structuring the Secunda secundae in terms of the three theological and four cardinal virtues concerns concision and efficiency: the path of enquiry will be more compendious and expeditious (‘compendiosior et expeditior’) if the virtues, the opposing vices, the commandments, and the gifts of the Holy Spirit are treated together.Footnote ⁵¹ Aquinas’s second reason is in keeping with the implications of his new rationale in De malo. In Aquinas’s schema, the vices are diversified in species with respect to their matter or object (‘secundum materiam vel obiectum’). As vices therefore operate in a disordered way with respect to the same objects as virtues, all moral matters may be traced back to them. Both of these reasons represent a major reform and innovation with regard to Peraldus’s approach. Peraldus’s rationale impels him to treat the vices and virtues separately: he structures De vitiis according to disordered love through excess or deficiency (gluttony, lust, avarice, and sloth) and to the love of an evil (pride, envy, and anger); he structures De virtutibus according to the theological and cardinal virtues, the gifts of the Holy Spirit, and the beatitudes. By relating vices to the virtues in terms of their shared objects, Aquinas is able to treat vices and virtues together within the virtues scheme, thereby avoiding unnecessary repetition. Even Aquinas’s further decision to treat primarily those moral matters relevant to all states of men (STh., IIa–IIae, qq. 1–170), and only secondarily those relevant to particular states (qq. 171–89), reflects another clear reform of Peraldus’s procedure.

Peraldus’s De vitiis et virtutibus and Dante’s Purgatory and Paradise

It is clear from this comparative analysis that Aquinas and Peraldus took very different approaches to the seven capital vices. Aquinas reforms the moral system of the seven capital vices from within: he provides an Aristotelian anthropology and develops a new positive teleological framework in which to set the vices. Moreover, in the Summa, he reorganises the vices as deviations from the true path of the virtues. Peraldus, by contrast, presents a two-stage journey: a journey from vice (with specific mirror virtues), followed by a journey to heaven (through the theological and cardinal virtues). In other words, where Peraldus’s rationale impels him to treat the vices separately, according to disordered love by excess or deficiency (gluttony, lust, avarice, and sloth) or to love of an evil (pride, envy, and anger), Aquinas’s Aristotelian anthropology enables him to treat vices and virtues together in terms of their shared good objects, either to be desired or avoided.

In structuring his own Christian ethics, therefore, Dante is following the older, more conservative tradition represented by Peraldus rather than the innovative reforms of Aquinas’s Summa Theologiae, IIa–IIae, which would supersede Peraldus’s Summa as the moral handbook for Dominican moral theology only in the course of the fourteenth century. The seven vices (with their corresponding remedial virtues, gifts of the Holy Spirit, and beatitudes) structure Peraldus’s De vitiis and the seven terraces of Dante’s Purgatory; the four cardinal virtues and the three theological virtues structure Peraldus’s De virtutibus and Dante’s Paradise. As the next three chapters demonstrate, Dante follows Peraldus not only in terms of his moral rationale for Purgatory, but also in his treatment of the seven vices and their individual subsidiary vices (henceforward ‘sub-vices’).

Moreover, the parallel organisation of ethical content is matched by a parallel in terms of form. The early-fourteenth-century Santa Maria Novella manuscript of William Peraldus’s De vitiis et virtutibus contains three beautifully illustrated initials depicting one or more Dominicans.Footnote ⁵² The first shows a Dominican passing on the treatise to another, which may reflect the treatise’s primary purpose as a key resource for pastoral ethics.Footnote ⁵³ The second (opening the treatise on the vices) shows a Dominican preaching against vice – his right index finger is raised in didactic pose, his eyes look down in stern admonition, and a red book is closed in his left hand; this may reflect the treatise’s oral diffusion to laymen as an instruction in morals and a call to penance.Footnote ⁵⁴ The third (opening the treatise on the virtues) shows a haloed Dominican unshadowed by the Sun – with an open book in his right hand, his left beckons his audience to follow the virtuous path to heaven.Footnote ⁵⁵ These three illuminations may illustrate the scope of Peraldus’s De vitiis et virtutibus as a whole: the treatise on the vices maps out man’s journey away from the perversion of sin; the treatise on the virtues, his path to his heavenly home. It is for this reason that, in another fourteenth-century manuscript, a later scribe has written (on the inside cover) that the treatise is, simply, a summa theologiae.Footnote ⁵⁶

The contrasting postures of the Dominican preacher towards his audience in De vitiis (the stern preacher against vice) and De virtutibus (the haloed Dominican welcoming his audience into the virtuous path to heaven) highlight an under-explored aspect about the relationship between the poet, Dante, and his intended audience in Purgatory and Paradise. Domenico di Michelino’s Dante e la Divina Commedia (1465) depicts Dante in exactly the same pose as the saint in the third illustration (Peraldus’s treatise on the virtues).Footnote ⁵⁷ This posture might seem appropriate for Dante’s Paradiso but, for the Purgatorio, we might better imagine Dante assuming the role of the vernacular preacher against vice.Footnote ⁵⁸ The corollary, of course, is that the reader of Dante’s Purgatorio is envisaged in the posture of a Christian sinner.Footnote ⁵⁹ There are obviously many other ways in which Dante’s second canticle can be, and has been, read (and, as we have already noted, some of these approaches have deliberately evaded the theological dimension tout court). Even so, it is historically compelling to explore how the perspective of preacher-poet and sinner-reader, invited by the parallels with Peraldus, might affect our reading of Purgatorio. With this approach to the ethical content and form of Dante’s Purgatory in mind, we now turn to the first terrace of Purgatory, the terrace of pride.