The question of what role the human mind plays in moralbehaviour—or the study of moral psychology—has been afruitful area of research in medieval philosophy since at least theearly to mid-1990s. Since then scholars have done much to illuminatemedieval contributions to such perennial topics as the freedom of thewill, the problem of moral weakness, and what role, if any, theemotions and the moral virtues play in the achievement of happiness(e.g., Kent 1995, Saarinen 1994, Dumont 2000, Eardley 2006, Hoffmann2007, and Osborne 2014). Similarly, metaethical theories about thefoundations of morality that were prominent during the medieval periodsuch as natural law theory—particularly in its Thomistic andScotistic variants—continue to receive robust scholarlyattention (e.g., Porter 2005, Möhle 2003, Lisska 2012, Sweeney2012, and Cross 2012). Comparatively less consideration, however, hasbeen devoted to what was believed to link the psychological to themetaethical: the mental habit or act of conscience (and itssister-concept of synderesis), though interest in the subject hasrecently seen a modest resurgence (e.g., Hoffmann 2012, Eardley 2013,and Dougherty 2018).

What is the scope and nature of this apparent ability to intuitivelygrasp right from wrong? Can conscience err and, if so, do its dictatesstill bind? The best way to address these and other questions is toemploy a developmental approach. The term conscience is stillgenerally used to refer to an innate moral sense, but it has slightlydifferent connotations today than it did in the medieval period, whichin turn had different connotations from what preceded it in paganantiquity and in Scripture. Still, medieval theories of consciencedrew extensively on these earlier sources. Since the concepts ofconscience and synderesis evolved over time, then, it will benecessary to take a linear approach to the topic and begin with somebackground.

• 1. Background: The Pagan and Early-Christian Context
  • 1.1 The Ancient Context: Judicial Conscience
  • 1.2 St. Paul: Legislative Conscience
  • 1.3 St. Jerome: The Invention of Synderesis
• 2. The Early-Scholastic Tradition
  • 2.1 Peter Lombard: The Scholastic Origins of the Debate
  • 2.2 Stephen Langton: Synderesis and its Properties
  • 2.3 Philip the Chancellor: The First Systematic Treatment of Synderesis and Conscience
• 3. The Later-Scholastic Tradition
  • 3.1 St. Bonaventure: Conscience as Cognitive/Synderesis as Affective
  • 3.2 St Thomas Aquinas: Synderesis and Conscience as Cognitive
  • 3.3 William of Ockham: New Directions in the Understanding of Synderesis and Conscience
• Bibliography
  • Primary Sources
  • Secondary Sources
• Academic Tools
• Other Internet Resources
• Related Entries

1. Background: The Pagan and Early-Christian Context

1.1 The Ancient Context: Judicial Conscience

To understand the medieval theory of conscience, it is essential toexamine its etymology. Unlike most philosophical categories that arecentral to medieval thought, the concept of conscience did not haveits origins in Plato or Aristotle (Potts 1982: 687). Rather, mostscholars agree, it originated in the Greek playwrights of the fifthcentury BCE (Sorabji 2014: 12, 15–18). It is also possible tofind its use elsewhere in Greek literature, such as in the fragmentsof Democritus (D’Arcy 1961: 5).

The English word “conscience” is derived from the Latinconscientia. Its Greek equivalent issyneidesis.Both terms connote a state or act of “sharing knowledge withoneself” (Sorabji 2014: 12). This knowledge is privileged andinvolves awareness of a personal moral defect. The notion that“I” can judge “myself” naturally suggests, asSorabji puts it, a sort of “split personality”. That is,it suggests that I can at once be both the judge and the one beingjudged, particularly with respect to specific, past actions whichordinarily elicit remorse. This suggestion is rooted in the quiteintuitive idea that human beings are reflexive animals: beings who arenot only capable of turning their attention to objects in the outsideworld but can also “turn back on” (reflectere) orbecome an object to themselves. As C. S. Lewis put it in his study ofthe concept of concept of conscience in the Western tradition:

Man might be defined as a reflexive animal. A person cannot helpthinking and speaking of himself as, and even feeling himself to be(for certain purposes), two people, one of whom can act upon andobserve the other. Thus, he pities, loves, admires, hates, despises,rebukes, comforts, examines, masters or is mastered by,“himself” […] He is privy to his own acts, is hisownconscius or accomplice. And of course, this shadowy inneraccomplice has all the same properties as an external one; he too is awitness against you, a potential blackmailer, one who inflicts shameand fear. (Lewis 1960: 187; see also Sorabji 2014: 12)

Lewis refers to this primarily pagan understanding of conscience as an“inner witness”. It does not judge our actions as right orwrong, but merely testifies to their existence:

It bears witness to the facts, say, that we committed a murder. Itdoes not tell us that murder is wrong; we are supposed to know that insome other way. (Lewis 1960: 190)

Others, however, regard the sort of conscience that Lewis describeshere as a type of internal judge, and therefore refer to it as“judicial conscience” (D’Arcy 1961: 8). While thisproperty of the mind does not necessarily issue binding rules, it doespass moral judgements on our deeds. It would, however, eventually takeon the role of issuing moral dictates for future acts as well. EricD’Arcy refers to this later form ofsyneidesis orconscientia as the “legislative conscience” whoseinnovator, he argues, was the Apostle Paul (ca. 5 CE–ca. 64/67CE), the most important founder of the Christian faith after Jesus ofNazareth (D’Arcy 1961: 8).

1.2 St. Paul: Legislative Conscience

The judicial understanding of conscience continued well into the firstcentury of the Common Era. To be sure, Paul himself continued toemploy it. At the same time, D’Arcy credited Paul withintroducing, in addition to the “judicial conscience”, anovel conception he termed the “legislative conscience”.It is not difficult to see why the earlier judicial conception wouldlater take on legislative features. This is because the ability tojudge past actions as either right or wrong—and to issueexhortations on that basis—would, once this property came to beassociated with the moral law, take on the legislative role of issuingcommands. Indeed, it is in St. Paul that we find this very associationbetweensyneidesis and the moral law:

[W]hen Gentiles, who do not have the law, do by nature things requiredby the law, they are a law for themselves, even though they do nothave the law. They show that the requirements of the law are writtenon their hearts, their consciences also bearing witness, and theirthoughts sometimes accusing them and at other times even defendingthem. (Romans 2:14–15; NIV)

Judging by this passage, there are evidently two expressions of themoral law according to Paul: The Mosaic Law, explicitly handed down tothe Jews, and another law that is “written on [men’s]hearts”. This latter was later glossed as a reference to thenatural law, which is accessible to all people, non-Jews included, andis consistent with the Mosaic Law. Notice that, according to theforegoing passage, conscience (syneidesis) is not theultimate source of right and wrong. Rather, the foundation of rightand wrong is the objective moral law, which is both “written on[men’s] hearts” and borne witness to by conscience.

One might say, then, that the objective norm of morality onPaul’s account is the moral law (or natural law). Conscience,however, might be termed morality’s subjective norm. This ismade clear in another passage from St. Paul, where he is addressingthe question of whether it is permissible for Christians to eat meatthat was previously sacrificed to idols. Some, Paul says, erroneouslythink that to eat such food defiles them. In fact, since the paganidols do not exist, eating food sacrificed to them, or indeed to Godhimself, is morally irrelevant, since “food does not bring usnear to God—we are no worse if we do not eat, and no better ifwe do” (1 Corinthians 8:8; NIV). Still, even though theconsciences of such Christians are erroneous, they must follow themsince conscience, Paul suggests, is a rule of conduct (Romans14:13–23). Eric D’Arcy sums up these two importantcontributions of St. Paul as follows:

St. Paul, then, introduces an entirely new phase in the history of theterm “conscience” in moral theory, and two new featurescharacterize his use of it. First, it is to play adirectiverolebefore action takes place. In the pagan writers,conscience did not appear on the scene untilafter the actionwas performed, and its role was purelyjudicial; but in St.Paul, conscience is credited with a legislative function, and itinduces an obligation in the proper sense. Second, conscience isfallible: the directions it issues may be mistaken; but whether it bemistaken or not, it seems that we are bound to follow its rulings.(D’Arcy 1961: 11–12)

In sum, we might follow Sorabji’s suggestion that this phase inthe development of the concept of conscience—that is, from itsorigins in fifth-century BCE Greek literature to the first-centuryCE—has eight features (Sorabji 2014: 36).

1. It involves a consciousness of the self rather than ofothers.
2. It draws on values to which one feels personally committed or thatare “not necessarily shared by others”.
3. It is self-reflexive insofar as it suggests a “splitperson”: an “I” that has secret knowledge which itshares with itself.
4. Its original purpose was “retrospective” or judicial,although it later incorporated into its definition a“prospective” or legislative function.
5. Although it draws on general moral principles, it is chieflyconcerned with their application to the specific circumstances inwhich the agent finds him or herself.
6. It began as a secular concept.
7. In the Christian tradition it is regarded as susceptible to error,and
8. although cognitive in character, it possesses motivating oraffective power.

1.3 St. Jerome: The Invention of Synderesis

That conscience was so central a concept in St. Paul’s writingsguaranteed it an important place in the moral theology of the Greekand Latin Fathers, especially St. Basil, John Damascene and St.Ambrose. Amongst these early writers, however, it was a text from St.Jerome that was particularly consequential since it introduced intothe debate a neologism that would have an important impact in thelater Middle Ages: the concept of synderesis.

In the course of commenting onEzekiel, Jerome had tied aprophecy mentioned in its first book to Plato’s moral psychology(commentaryon Ezekiel 1.7). The prophecy in questionconsisted of a vision of four creatures emerging from the heavens,each with four faces: those of a man, a lion, an ox and an eagle(Ezekiel 1: 4–14). In his gloss, Jerome noted that “mostpeople” (plerique) interpreted this vision withreference to Plato’s tripartite division of the soul in theRepublic: the human face representing reason, thelion’s face the spirited part, and the ox’s face theappetitive part (cf. Plato,Republic, 436b–441b). Whatdid the eagle represent? According to Jerome, it represented that“spark of conscience” (scintilla conscientiae)which makes us aware of our sinfulness when reason, spirit or desirebecome disordered. Medieval manuscripts refer to this psychologicalproperty assynderesis (or sometimessynteresis):

Now above these three was the eagle; so in the soul, they say, abovethe other three elements and beyond them is a fourth, which the Greekscallsynderesis. This is that spark of conscience which wasnot quenched even in the heart of Cain, when he was driven out ofparadise. This it is that which makes us, too, feel our sinfulnesswhen we are overcome by evil Desire or unbridled Spirit, or deceivedby sham Reason. It is natural to identify synderesis with the eagle,since it is distinct from the other three elements and corrects themwhen they err […] However, we also see that this conscience(conscientia) is cast down in some people, who have neithershame nor insight regarding their offences, and loses its place[…]. (commentaryon Ezekiel 1.7; D’Arcy trans.1961: 16–17)

Most scholars now agree that the neologism “synderesis”introduced in Jerome’s commentary is simply a corruption of theGreeksyneidesis (Kries 2002: 67). Sincesyneidesisis simply the Greek equivalent of the Latin termconscientia—a fact of which Jerome would certainly havebeen aware—one might have expected Jerome to use theminterchangeably. Surprisingly, however, Jerome suggests that the Latinterm means something different from the Greek term. In the text citedabove, he quite explicitly states that regardless of how morallycorrupt its possessor becomes, synderesis can never be lost. A fewlines later, however, he does admit the existence of those who areshameless and lacking in moral insight. Such people are oblivious totheir offenses because, according to Jerome, their conscience(conscientia) ceases to be present in them (“looses itsplace”). If synderesis cannot be lost, but conscience can, thenit seems to follow that they are separate properties of the soul. Inany case, whatever Jerome’s intention, this curious passage wasindirectly handed down to the Middle Ages via theSentencesof Peter Lombard (1095–1160).

2. The Early-Scholastic Tradition

2.1 Peter Lombard: The Scholastic Origins of the Debate

Peter Lombard’s role in the evolution of the concept ofconscience is both surprising and unsurprising. It is—at firstsight, anyway—surprising because Lombard does not discussconscience or synderesis in any actual detail. Indeed, he does not,strictly speaking, mention the terms “synderesis” or“conscience” at all. What he does is merely to allude toJerome’s commentary onEzekiel in the context ofdiscussing the will’s role in how rational agents can naturallywant what is good while simultaneously being slaves to sin (PeterLombard,Sententiae in IV libros distinctae, 2.39; Potts1980: 92). In St. Paul’s reference to moral weakness in Romans7:15, he famously says: “For I do not do what I want but do whatI do not want”. Is Paul suggesting, asks Lombard, that we havetwo separate wills: one naturally oriented towards the good andanother oriented towards sin? Or is it rather the case that we have asingle will that, although naturally inclined to the good, contains adefect which also “takes pleasure in what is evil”(Sententiae in IV libros distinctae, 2.39; Potts 1980: 93)?Amongst those who hold the first view, the motivating power thatorients us towards the good is called the “natural” will,while the inclination towards sin resulting from the Fall is called“free will” (or “free choice”). With respectto the former, Peter writes:

For some say that there are two motivations, one by which a mannaturally wants what is good. Why naturally? And why is it called“natural”? Because such was the motivation of human naturein its original state, in which we were created without any defect,and this is properly called “nature”. For man was createdwith a righteous will […] Man is therefore rightly saidnaturally to want what is good, because he was constructed with a goodand righteous will. For the higher spark of reason (superior enimscintilla rationis) which, as Jerome says, “could not evenbe extinguished in Cain”, always wants what is good and hateswhat is bad. (Peter Lombard,Sententiae in IV librosdistinctae, 2.39; Potts trans. 1980: 92–93)

Lombard’s brief mention of Jerome’s “spark ofreason” (sic) in the aforementioned passage is the full extentof his treatment of conscience and synderesis. Still, that wassufficient to ensure that it would receive robust attention by laterscholastics, who would track down the original text from Jerome inorder to comment on it. A compilation of theological writings takenmainly from Scripture and the Fathers and arranged in systematicfashion, theSentences had an enormous impact on latertheological enquiry since much it, after the 1220s, was carried outwithin the taxonomy that Lombard had laid out in his work. Indeed,after Alexander of Hales (1185–1245) adopted theSentences as the main source for his ordinary lectures atParis in 1222, and Richard Fischacre (1206–1248) did the same atOxford in 1245, lecturing on theSentences became arequirement for every aspiring master of theology. Thus did such majorscholastics of the thirteenth and fourteenth centuries as Bonaventure(1221–1274), Thomas Aquinas (1224/25–1274), John DunsScotus (1265–1308) and William of Ockham (1287–1347) cometo write their important commentaries on the work. This traditionwould continue well into the sixteenth century.

Consisting of four books, each subdivided into chapters, theSentences follows the distinction that Saint Augustine haddrawn in theDe doctrina Christiana between the things thatare real and the signs that lead us back to the former. Book onetreats of God, who is really real, and his triune nature. Book twodeals with creation and the fall, including human nature, treatingthese as signs that point back to God. Book three treats of Christ,who is the antidote to the fall, and who, as God incarnate, is boththing and sign. Finally, book four treats of the sacraments, which aresigns that assist the fallen in their return to God: the ultimatereality. Since book two deals with human moral psychology in thecontext of creation and the fall, it is here, in distinction 39, thatPeter Lombard’s mention of Jerome’s commentary onEzekiel is found.

Since Lombard’s treatment of Jerome was partial and elliptical,later thinkers, in composing their commentaries on theSentences, naturally turned to Jerome’s text in orderto scrutinize the original passage. There, they discovered hisapparent distinction between synderesis and conscience, which in turnwould come to frame the parameters of the later medieval debate. Ifsynderesis and conscience are in fact two separate parts of the soul,for instance, what is their relationship to one another? What, come tothat, are their respective natures and, rather importantly, can theybecome disordered? Such questions would preoccupy the theologians ofthe later Middle Ages.

2.2 Stephen Langton: Synderesis and its Properties

Stephen Langton (1155–1228), regent master of theology at Parisand later Archbishop of Canterbury, is important in the presentcontext less for any systematic treatment of conscience—indeedStephen scarcely touches on the issue at all—than for hissomewhat scattered views on synderesis. The relevant treatment comesin Stephen’sQuaestiones disputatae of 1203–1205in the context of his discussion on free decision (liberumarbitrium).

For Stephen, there are three powers (vires) of the soul thatare relevant to the moral life: the concupiscible appetite, reason andsynderesis. The concupiscible appetite draws reason towards what isbad—specifically towards the sin of sensuality—whilesynderesis attempts to sway it towards the good. It is reason’sjob to adjudicate between these two impulses. Freedom of decision(libertas arbitrii) is the outcome of reason directing thewill to choose in accordance with either the promptings of sensuality,or the promptings of synderesis (Stephen Langton,Quaestionesdisputatae; Lottin ed.Psychologie et morale I, 1942:61).

The purpose of synderesis, then, is to direct reason away from vicefor it is the faculty “by which a person naturally detests whatis evil and is a part of the rational power” (Quaestionesdisputatae; Lottin ed.Psychology et morale II.1, 1948:112). Can such a power be extinguished? Yes and no. In its capacity asan inclination towards the good, which is accidental to it, synderesiscan indeed be lost in the damned. Essentially speaking, however, thepurpose of synderesis is to repudiate what is wicked. In this sense,it is never lost, even in the damned (Quaestiones disputatae;Lottin ed. 1948: 111).

Stephen Langton’s most important contribution to the developmentof the concept of synderesis occurs in his discussion of whethersynderesis can merit or demerit. In the process of discussing thisissue Stephen links synderesis to the practical syllogism,specifically associating it with the grasp of general principles(Quaestiones disputatae; Lottin ed. 1948: 113). D’Arcysums up Langton’s position as follows:

Remorse of conscience is the work, not of synderesis, but of reason,for synderesis remains at the level of general principles, whereasreason descends to the concrete case; but it is precisely over theconcrete case that remorse of conscience is felt; hence it is byreason, and not by synderesis, that we sin. (D’Arcy 1961:23–24)

Langton’s association of synderesis with general moralprinciples would, as we will see, influence later thinkers such asAquinas.

2.3 Philip the Chancellor: The First Systematic Treatment of Synderesis and Conscience

Although Stephen Langton was the first scholastic to touch on theissue of synderesis in any depth, it was Philip the Chancellor (ca.1170–1237) who wrote the first treatise devoted to exploring therelationship between synderesis and conscience (Lottin 1948:139–157). As chancellor of Notre Dame, Philip had the right togrant the license to teach in the theology faculty at Paris, and itwas under his tenure that the Dominicans and the Franciscans acquiredtheir chairs in theology: two for the former, and one for the latter.Although primarily an administrator, Philip was also a trainedtheologian. His most important work is theSumma de bono,which includes the treatise on conscience.

In his treatise Philip sets out to answer several questions related tothe ontological status of synderesis, to the question of whetheranyone can sin if they follow synderesis, and to whether it can everbe extinguished. As to the ontological status of synderesis, Philipcites Jerome’s authoritative suggestion that synderesis is afaculty or power of the soul. Recall that Jerome had posited aquadripartite soul: one that is composed of reason, spirit, desire andsynderesis. Since the first three parts of the soul are potentialitiesand synderesis is classified alongside these, it seems to follow thatit too must be a faculty or power of the soul, distinct from thefaculty of reason. Philip cites St. Paul and John of Damascus ascorroborating authorities who apparently share the view thatsynderesis is a faculty of the soul independent of the others (Philipthe Chancellor,Summa de bono: Treatise on Conscience; Pottstrans. 1980: 95–96).

Against the claim that synderesis is a power of the soul, Philippresents arguments for the view that it is, on the contrary, a moralhabit. On this view, synderesis is to the natural will what choice isto the deliberative will: a disposition that regulates the rationallyappetitive powers. But while choice simply regulates the deliberativewill with respect to the contingent good, or means towards happiness,synderesis

is a disposition arising naturally in conjunction with thatpotentiality by which the natural will is directed to what is goodwithout qualification. (Summa de bono: Treatise onConscience; Potts trans. 1980: 96)

Moreover, just as the impulse to sin is distinct from the soul, so toois synderesis. But whereas the former inclines the agent towards evil,the latter inclines him towards goodness.

Is synderesis, then, a power of the soul or a habit? This distinctiongoes back to Aristotle, for whom powers are innate and associated withspecific capacities, while habits are acquired and associated, bycontrast, with tendencies to behave in certain ways. Habits, moreover,inhere in powers. Although both of these properties dispose the agentto act in particular ways, powers, in contrast to habits, are linkedto the ability to do so contingently. If I am in the habit of speakingRussian, for instance, then I will have the tendency to do so on aregular basis. It is my preferred mode of communication, and I willtake every opportunity to express myself in that language. That I mayhave the mere capacity—or power—to speak Russian, on theother hand, having studied it in school, say, in no way ensures that Iwill do so even in situations where I probably should. I might, forexample, hate and resent speaking Russian for various reasons, andtherefore freely refuse to do so under any circumstances (see, e.g.,Aristotle,Metaphysics 9.2, and Potts 1980: 20–22).

Although Philip seems to favour the belief that synderesis is a habit,the claim that it is a power of the soul has the rather weightyauthority of St. Paul and St. Jerome. Philip therefore splits thedifference, as it were, and argues that it is a “habit-likepower” or “dispositional potentiality”(habitualis potentiae)—a faculty of the soul thatdisposes its possessor towards choosing the unqualifiedgood—though one that is innate rather than acquired throughhabituation:

Synderesis, although the morphology of its name makes itsound more like a disposition than a potentiality, is nevertheless thename of a dispositional potentiality: I do not say of an acquireddisposition, but of an innate one. And thus,qua dispositionit can be applied to what is related to it as a disposition,qua potentiality to what is related to it as a potentiality.From this it follows that it has a certain opposition to free choice,a certain opposition to the impulse [to sin] and sensuality, and acertain opposition toproheresis, which is part of freechoice:qua potentiality, it is disparate from free choiceand from sensuality,qua disposition it is disparate fromproheresis and the impulse [to sin]…So, if anyone askswhether it is a potentiality or a disposition, the right answer liesin taking something in between: a dispositional potentiality.(Summa de bono: Treatise on Conscience; Potts trans. 1980:97)

It would seem, then, that synderesis is a potentiality, albeit anunusual one. Is it connected to the cognitive side of the soul or tothe appetitive? According to Philip, it is related to the appetitive,and specifically to the rational appetite, that is, to the will,rather than to the sense appetite. However, as we saw, Philip dividesthe rational appetite into what he calls “natural will”and “deliberative will”. The natural will signifies thegeneral inclination that humans have to the good or happiness as such.Such an object is beyond the scope of choice. Having said that,happiness can be achieved in any number of ways and by the acquisitionof any number of legitimate, though contingent goods. Indeed, it isfair to say that rational agents never choose happinessassuch, given that it is a mere abstraction. Rather, what theychoose are particular goods which, taken together, comprise the goodlife if pursued in an orderly way. Such contingent goods are the meansto happiness and are the objects of the deliberative will, andtherefore choice. Synderesis, according to Philip, pertains to thenatural will. It is the remnant of original rectitude or justicewhich, although damaged during the fall, remains in the soul indiminished form. As Philip puts it, synderesis is that which“murmurs back against sin and correctly contemplates and wantswhat is good without qualification” (Summa de bono: Treatiseon Conscience; Potts trans. 1980: 100).

On the matter of conscience and how it is related to synderesis,Philip distinguishes them. For one thing, conscience can be mistakenwhile synderesis cannot. Specifically, conscience is the result of aconcurrence of synderesis with free decision (liberumarbitrium). Put otherwise, it is the specific application of ageneral moral principle that is the outcome of deliberation. Whencorrectly applied, conscience is correct. When incorrectly applied, iterrs. In either case, the judgement of conscience generates a moralobligation to act. Philip uses the following example of howsynderesis, which is always right, can nonetheless conjoin with anerring conscience (Potts 1980: 104):

1. Unerring universal premise of synderesis: “Everyone whofalsely claims to be the Son of God should be put todeath”.
2. Erring minor premise of reason: “This Christ fellow isfalsely claiming to be the Son of God”.
3. Erring judgement of conscience: “Therefore this Christfellow should be put to death”

From the foregoing example, it is clear that synderesis delivers ageneral, non-deliberative proposition, while conscience yields whatPotts calls a particular, “deontic proposition”:

Philip’s argument is […] that we need to distinguishbetweengeneral andparticular propositions whichare of the form: “A ought to φ” where theproper name of any person may be substituted for“A” and any verb-phrase containing a verb of actionfor “φ” (I shall henceforth call these “deonticpropositions”). (Potts 1982: 690–692)

In the example given above, then, the first, universal premise iscorrect (by definition), while the conclusion, as mediated by erringreason, generates an incorrect deontic proposition, which is to say,an obligation to act, albeit a mistaken one.

3. The Later-Scholastic Tradition

3.1 St. Bonaventure: Conscience as Cognitive/Synderesis as Affective

One of the most prominent representatives of the Franciscanintellectual tradition, Bonaventure (1217–1274) lectured on theSentences at Paris from 1250 until 1252, when he becameregent master in the theology faculty, a position he held until 1257.His commentary on theSentences is the fruit of theselectures, and it is in this work that he discusses the topics ofconscience and synderesis. For Bonaventure we not only possess innatemoral knowledge, but we also have an inextinguishable inclinationtowards achieving the good. Our inborn knowledge of the former, thatis, of the natural law, is associated with conscience, which residesin the intellect, while our inclination towards desiring the good isassociated with synderesis, which inheres in the will.

What is the ontological status of conscience? According toBonaventure, just as theologians have disagreed over the nature of“thought”, defining it variously as the power of thinking,a habit or an apprehended principle of knowledge, so too have theydiffered over how to define “conscience”(conscientia). Most commonly, however, the term has been usedto refer to a cognitive habit or disposition that relates to thepractical as opposed to the theoretical intellect. Indeed, it is thedisposition that perfects the practical intellect. How so? Through itsconsciousness of the principles that comprise the naturallaw—such as that “God is to be honoured”—andthrough the issuing of such injunctions to the will. As Bonaventureputs it:

theoretical knowledge perfects our thought to the extent that thelatter is theoretical, whereas conscience is a disposition perfectingour thought to the extent that it is practical, or to the extent thatit directs us towards deeds. (Bonaventure, commentary on theSentences, 2.39: a. 1, q. 1; Potts trans. 1980: 111)

Is such a disposition innate or acquired? It is possible, according toBonaventure, to find authorities on both sides of the debate. For theopinion that conscience is innate, Bonaventure cites, among otherauthorities, St. Paul’s famous reference to a moral law that is“written on [men’s] hearts” in Romans 1:14–15.He also appeals to a “natural instinct to seek blessedness and[to] honor [one’s] parents” (commentary on theSentences, 2.39: a. 1, q. 2; McGrade trans. 2001:175–176). For the opinion that conscience is not innate, on theother hand, Bonaventure cites Aristotle’s claim that the soul isa blank slate. Bonaventure’s solution is to find a middleposition between St. Paul, on the one hand, and Aristotle, on theother. His conclusion: conscience is part innate, part acquired.

In what sense is it innate? Just as rational creatures have a naturalcapacity to judge the veracity of first principles in the realm ofspeculative reason, so we have an innate capacity to judge the firstprinciples of practical reason. This innate capacity to immediatelygrasp such principles as true or not in the realm of practical reasonis called conscience. It is associated, for Bonaventure, with theAugustinian “natural light”—or “naturaltribunal”—that is built into the structure of the mind andwhich permits rational agents to intuitively grasp the basicprinciples of the natural law (see, e.g., Augustine,City ofGod, 11.27, Bettenson trans. 1972: 461–462). Just as themind is disposed to grasp, in the realm of theoretical reason, theaxiomatic nature of such propositions as that “all bachelors areunmarried males”, so too it has a innate disposition to grasp asself-evidently true such basic principles in the domain of practicalreason as “Honour thy father and mother” and “Do notharm thy neighbour”.

In what sense, though, is conscience acquired? Although the ability tojudge the deontic propositions of the natural law as self-evidentlytrue is innate, it does not follow that thecontents of suchpropositions are innate. It does not follow, that is, that theconcepts “father” and “mother” in the preceptto honor one’s parents are in the mind from birth. And indeed,so Bonaventure thinks, they are not. Rather, they are species orlikenesses acquired through sense experience which, once acquired,form the terms of the universal propositions of the natural law thatare intuitively grasped. In this sense, Bonaventure is true toAristotle:

For everyone agrees that there is an imparted light of theapprehensory potentiality which is called a natural tribunal, but weacquire forms and likenesses of things by means of the senses, asAristotle says explicitly in many places, and as experience alsoteaches us. (commentary on theSentences 2.39: a. 1, q. 2;Potts trans. 1980: 113)

Conscience, then, is partly innate and partly acquired with respect tothe content of the natural law. But what is the relationship of suchuniversal premises to the conclusions of practical reason? How doesthe agent proceed from a general knowledge of right and wrong to theapplication of this knowledge to concrete situations? After all, suchuniversal premises are only useful to the extent that they can beapplied. For Bonaventure, the habit of directing the agent towardapplying the general principles of the natural law to specificactions, like the habit of immediately grasping deontic principles, isinnate. But in order to apply this self-evident knowledge we mustacquire further knowledge. For example, although we graspapriori the truth that one should honor one’s father andmother, we have no innate knowledge that John and Mary are our parentsand that it is they specifically who must be honoured as opposed to,say, Michael and Jane. Rather, this type of knowledge is derived fromexperience and instruction.

Note that conscience does not simply move from the general to theparticular with respect to concrete actions. It also moves from thegeneral to the specific with respect to propositions themselves. AsPotts points out, there are in fact two classes of deonticpropositions: basic and derived (Potts 1982: 698). Consider thedeontic proposition to obey God, which is basic, or maximally evident.Obviously, other more specific precepts can be derived from this verygeneral one. Historically, for instance, from the basic deonticproposition to obey God the Jews derived the further, less evident butmore specific deontic propositions to refrain from eating pork and tocircumcise their sons. How did they come to know these more specificpropositions? By means of a revealed commandment—via (divine)instruction, in other words (commentary on theSentences2.39: a. 2, q. 3, ad 4; Potts trans. 1980: 120). Although thedistinction between basic and derived deontic propositions isPotts’, and although the case cited is an example of anerroneous conscience (Bonaventure argues that male circumcision andthe prohibition on eating pork are no longer applicable), itaccurately sums up Bonaventure’s distinction betweenpropositions that are “very clearly evident” versus thosethat are “less evident”:

Just as some things that are cognizable are very clearly evident, suchas axioms and first principles, while some are less evident, such asparticular conclusions, so also in things that can be done, some areevident in the highest degree, for example, “Do not do toanother what you do not want done to you” and that one shouldsubmit to God and suchlike. In the same way, then, as the cognition offirst principles is said to be innate in us by reason of that light,because (due to their self-evidence) that light suffices for cognizingthem (after the reception of species) without any additionalpersuasion, so also the cognition of moral first principles is innatein us, in that that judicatory suffices for cognizing them. Again, inthe same way as cognition of the particular conclusions of thesciences is acquired, because the light innate in us does not fullysuffice for knowing them, but some persuasion and fuller acquaintanceare needed, so on the side of things that can be done we mustunderstand, similarly, that we are bound to do some things which weknow only through additional instruction. (commentary on theSentences 2.39: a. 1, q. 2; McGrade trans 2001: 179)

This distinction between basic, or very general principles, andspecific or derived precepts is germane to the question of whetherconscience can ever be mistaken and, if so, whether in such cases itcontinues to bind. Bonaventure’s response is that we can neverbe mistaken about basic deontic propositions. Rather, it is withrespect to derived ones that we sometimes err since

although conscience is always right so long as it sticks to thegeneral and is moved by simple inspection, it can become mistaken whenit descends to particulars and brings things together, because theactualisation of deliberative reason is mixed with it. (commentary ontheSentences 2.39: a. 2, q. 3, ad 4; Potts trans. 1980:120)

Is one obliged to always follow one’s conscience? It depends,since conscience is fallible. If what it dictates is in accordancewith God’s will, then one is obliged to follow it on pain ofeternal damnation. If erroneous—if what it dictates is contraryto the divine will—as is sometimes the case when applying basicdeontological principles, then conscience does not bind. Rather, theagent has an obligation to correct the error in order to bring hisconscience into line with the natural law. If he does not, and followshis erroneous conscience, he commits a mortal sin. “It is clearthatconscientia always either binds us to do what it tellsus, or binds us to change it” (commentary on theSentences 2.39: a. 1, q. 3; Potts trans. 1980:114–115). Obviously, then, the intellect plays an important rolein achieving happiness given its possession of conscience. But what ofthe will? Does it not have an equally important role to play in themoral life? Yes: in its possession of synderesis. In line withtradition, Bonaventure calls synderesis the “spark ofconscience” (commentary on theSentences 2.39: a. 2;McGrade trans. 2001: 186). He breaks with tradition, however, inarguing that it inheres in the will rather than in the intellect.Indeed synderesis, for Bonaventure, is precisely the counterpart ofconscience insofar as the will, like the intellect, has an innateinclination towards the moral (as opposed to the useful) good. In thecase of the intellect this disposition takes the form of the“natural light” of conscience that apprehends the firstprinciples of the natural law; in the case of the will, it takes theform of synderesis: a “natural bias” towards desiring themoral good. There is one sense, however, in which synderesis is notexactly analogous to conscience. While it looks very much like ahabit, synderesis is rather, according to Bonaventure (presumablyfollowing Philip the Chancellor), a habit-like power of the soul(commentary on theSentences 2.39: a. 2, q. 1; Potts trans.1980: 116–117).

Can synderesis ever be extinguished? No: it is an innate orientationtowards goodness that cannot be completely eradicated, ontologicallyspeaking, even in the most vicious of people. In its exercise,however, it can become impeded “either by the darkness ofblindness, or by the wantonness of pleasure, or by the hardness ofobstinacy” (commentary on theSentences 2.39: a. 2, q.2; Potts trans. 1980: 117). In such cases, synderesis ceases to“murmur” against evil or “goad” towards thegood, either because the agent is blinded by ignorance, distracted byphysical pleasure or is so stubbornly persistent in their depravitythat they cannot reorient themselves towards the good. Still, whensynderesis follows the innate judgement of conscience with respect tobasic deontic principles, which can never err, then it too functionscorrectly because that is its natural state. It has the potential togo wrong and fall into sin only during the exercise of deliberationwith respect to particular truths since it is here that reason canbecome faulty and the will, which is free, disordered. When reason andwill malfunction synderesis is “overthrown, in that its effectand its government over the other deliberative powers is repulsed andbroken” (commentary on theSentences 2.39: a. 2, q. 3;Potts trans. 1980: 119). When this happens, the agent sins.

3.2 St Thomas Aquinas: Synderesis and Conscience as Cognitive

Thomas Aquinas (1224/25–1274) is, by any measure, one of themost important, if not the most important, scholastic theologian ofthe later Middle Ages. Although his views on conscience and synderesishave received less attention in recent years than his theory ofnatural law, this is unjustified. For the scholastics, a full accountof morality includes not only an explanation of how practical normsare grounded, but also an understanding of how they are grasped andhow it is that rational agents, despite possessing an infallible guideto such knowledge, often fail to apply it. One’s metaethics, inother words, is inextricably linked to one’s moral psychology,which is to say, to one’s understanding of how the will and theintellect interact with one’s knowledge of right and wrong.

Aquinas discussed the issues of synderesis and conscience in severalof his major works, from his early commentary on theSentences and theDe veritate to his matureSumma theologica (see D’Arcy 1961: 36–47). Asmight be expected, his account is very different from that of hisFranciscan contemporary Bonaventure. For one thing, Bonaventureassigns synderesis to the will. He also describes it, as we saw above,as a “habit-like faculty”. Aquinas, as might be expected,hews much closer to his Dominican mentor and teacher Albert the Great(ca. 1200–1280) for whom both synderesis and conscience belongto the intellect (see Dougherty 2018: 221).

For Aquinas, the rational part of the soul comprises the faculties orpowers of intellect and will. The object of the will is the good, andthe object of the intellect is the true. The latter potency is furtherdivided into the speculative intellect (intellectusspeculativus) and the practical intellect (intellectuspracticus). How do these differ? The object of the speculativeintellect is truth as such, while the object of the practicalintellect is the good “under the aspect of truth” (ThomasAquinas,Summa theologica I, q. 79, a. 11, ad. 2). Synderesisand conscience, for Aquinas, both belong to the practicalintellect.

All reasoning must start from immediately evident principles if aninfinite regress is to be avoided. This is as true in the realm ofpractical reason as it is in the realm of speculative reason. Oncesuch principles have been grasped and assented to, more specificconclusions can be deduced. How are these principles grasped? In thedomain of speculative reason, they are apprehended by the innatedisposition that Aquinas callsintellectus—“intuitive reason” or“understanding”—and that Aristotle callednous. The objects of this habit are such self-evidentpropositions as that “every whole is greater than itspart” and that “things equal to one and the same are equalto one another” (Summa theologica I-II, q 94, a. 2,corp.). Once their terms are known, the intellect immediately graspsthe truth of such propositions since they are analytic in nature. Thecorresponding habit in the domain of practical reason, on the otherhand, is synderesis: a property of the soul which can never be lost,which never errs, and whose objects are the first principles of thenatural law (De veritate 16.1, corp.). A good description ofhow Aquinas understands synderesis is Hoffmann’s, who calls itan “infallible moral awareness” (Hoffmann 2012: 255). Likeunderstanding, synderesis is innate:

Wherefore the first practical principles, bestowed on us by nature, donot belong to a special power, but to a special natural habit, whichwe call “synderesis”. Whence “synderesis” issaid to incite to good, and to murmur at evil, inasmuch as throughfirst principles we proceed to discover, and judge of what we havediscovered. It is therefore clear that “synderesis” is nota power, but a natural habit. (Summa theologica I, q. 79, a.12, corp.)

In broad terms, synderesis is a link between the human intellect andthe divine wisdom. The universe is created and governed by aprovidential God and is therefore subject to the order of finalcausality. Accordingly, all things, rational and non-rational alike,seek their proper ends. Non-rational beings, since they lack will andintellect and are therefore incapable of prudential reasoning, achievetheir ends through the natural inclinations that are implanted in themby God. In this sense, they participate in the providential plan forall creation that Aquinas calls the “eternal law”: thedivine wisdom insofar as it directs all creatures towards their ends(Summa theologica I-II, q. 93, a. 1, corp.). They do so,however, in a diminished way. Rational beings, by contrast,participate in divine providence in a more excellent way. Thisparticipation in the eternal law is called the natural law, whosemoral principles function to direct human beings toward their ultimateend: happiness (Summa theologica, I-II, q. 91, a. 2, corp.).These moral principles, which are grasped and accordingly possessed bysynderesis, offer an insight into God’s intentions for humanbeings and therefore into the ultimate purpose of human life. AsBaylor writes of Aquinas’s theory:

Moral principles are based upon and derived from a rationality that ispresent in reality; they are a human knowledge of the exemplary ideasin the divine mind according to which creation is imbued with arational order. (Baylor 1977: 46)

Practical reasoning, then, plays a central role in the achievement ofhappiness, the final end for humans, and therefore in God’s planfor us. Like speculative reasoning, practical reasoning generallytakes a deductive form. Just as science is the conclusion of thedemonstrative syllogism, so conscience is the conclusion of apractical syllogism. The practical syllogism, like the demonstrativesyllogism, contains a major premise, a minor premise and a conclusion.The major premise is drawn or deduced from synderesis. The minorpremise, on the other hand, is drawn either from faith, natural reasonor human positive law. From the major and minor premises, a conclusionis drawn that generates a moral obligation to act (Hoffmann 2012:258). This inferential judgment is associated, for Aquinas, withconscience: an act—as opposed to a faculty or a habit—thatincludes a number of applications, such as “to witness, to bind,or incite, and also to accuse, torment, or rebuke” (ThomasAquinas,Summa theologica I, q. 79, a. 13, corp.).

Conscience acts as a “witness” when it is consciouslyaware of some personal wrongdoing, whether of commission or omission.It “binds” or “incites” when it makes ajudgement that some act should be performed. Finally, it“accuses”, “torments” or “rebukes”when it judges that some past action was either morally acceptable orit was not. Although it is difficult to see how conscience in thefirst sense—conscience as witness—can function as anapplication of knowledge to conduct, this seems less problematic inthe second and third senses of the term, which harken back to thelegislative and judicial senses of conscience found in St. Paul andpagan antiquity, respectively (D’Arcy 1961: 46). In any case, anexample of the way in which conscience applies the naturallaw—whose principles are apprehended by synderesis— isarticulated in Aquinas’sDe veritate:

If the judgement of synderesis expresses the statement: “nothingprohibited by the law of God is to be done”, and if theknowledge of higher reason presents this minor premise “sexualintercourse with this woman is forbidden by the law of God”, theapplication of conscience will be made by concluding: “thissexual intercourse is to be avoided”. (De veritate, q.17, a. 2, corp.; cited in Dougherty 2018: 222)

Now the dictates of conscience can either be right, if correctlydeduced from the natural law, or wrong, if they are incorrectlydeduced. The dictates of the former are the product of a“correct conscience” and the judgements of the latter arethe result of an “erroneous conscience”. Since synderesisis infallible, the main source of an erroneous conscience, when itdoes occur, is the agent’s adoption of a faulty minor premise inthe practical syllogism (De veritate q. 17, a. 2; Pottstrans. 1980: 132–133).

Now it is clear that we have an obligation to follow a correctconscience since to do so contributes to achieving our final end. Butwhat of an erroneous conscience? Does this have any authority? ForAquinas, an erring conscience also binds. It does not, however,necessarily excuse. As Hoffmann puts it,

regardless of whether my action is objectively good, evil orindifferent, conscience binds, for it is by means of conscience thatan action is proposed to me as good, bad, or indifferent. (Hoffmann2012: 260)

For example, it is objectively right—in accordance with thenatural law—to refrain from sex outside of marriage. But supposethat an agent (mistakenly) believes that such abstinence is sinful,and yet still refrains. According to Aquinas, this agent, although hedoes what is objectively right, nonetheless sins. Why? Because inchoosing the opposite of what his conscience dictated, he chose to dosomething he believed to be evil. And choosing what is (subjectivelyif not objectively) wrong, for Aquinas, is a sin: “[F] from thevery fact that a thing is proposed by the reason as being evil, thewill by tending thereto becomes evil” (Summatheologica, I-II, q. 19, a. 5, corp.).

What follows from this is that conscience, whether right or erroneous,always binds. As to the question of whether an erroneous conscienceexcuses, on the other hand, that depends on the type of ignorance thatcauses it. This is because some types of ignorance render an actinvoluntary and therefore excusable, and some do not. Ignorance thatexcuses is called invincible, and concerns ignorance about the factsof the situation (assuming, of course, there is no negligenceinvolved). Such cases, that is, where an agent could not have knownbetter under the circumstances and would not have thus acted had heknown better, are excusable. Aquinas uses the example offornication—voluntary, illicit sex—to illustrate hispoint. Although it is a sin to commit adultery, a man is excused if hehas sexual relations with a woman who is not his wife, so long as heis genuinely, if improbably, mistakes the women for his wife. Thisis

because this error arises from ignorance of a circumstance, whichignorance excuses, and causes the act to be involuntary. (Summatheologica I-II, q. 19, a. 6, corp.)

Ignorance that contributes to an erroneous conscience that is in anyway voluntary is vincible, or able to be corrected, and thereforeculpable if followed. This generally happens where the agent’signorance of the particulars of the situation is either the result ofnegligence, or where there is ignorance of the relevant moralprinciples. The former cases are the result of the agent not takingappropriate care to find out about the facts of situation so that heor she can sin while feigning ignorance. In the case of one’signorance of universal premises, this too is culpable since it isone’s obligation to know the moral law. (Summatheologica I-II, q. 19, a. 6, corp.).

But one might be wondering how it is that culpable ignorance is evenpossible where it relates to general moral principles. How can one gowrong about the universal premises that form the major premise of thepractical syllogism, which are drawn from the precepts which comprisethe natural law, if synderesis, which grasps such premises, isinfallible? Aquinas’s answer is that there are two types ofnatural law precepts: primary—or those which are “mostgeneral”—and secondary. Aquinas is less specific on thistopic than is optimal, but in drawing this distinction he seems tomean something like the following. About the primary precepts of thenatural law, no-one can go wrong. Unfortunately, as we have seen, suchprecepts are of a very general character, such as “do good andavoid evil”. For such general knowledge to be applicable byconscience, it must be further specified. This further specificationcomprises the secondary precepts of the natural law, which are closelydrawn from the former precepts and from natural inclination. Aboutsuch secondary, derived precepts of the natural law, such as“adultery is to be avoided”, humans are all too prone tobecome ignorant. For Aquinas such ignorance is the result either ofvice or of having been socialized in a culture with “viciouscustoms”:

I answer that […] there belongs to the natural law, first,certain most general precepts, that are known to all; and secondly,certain secondary and more detailed precepts, which are, as it were,conclusions following closely from first principles. As to thosegeneral principles, the natural law, in the abstract, can nowise beblotted out from men’s hearts. […] But as to […] thesecondary precepts, the natural law can be blotted out from the humanheart, either by evil persuasions, just as in speculative matterserrors occur in respect of necessary conclusions; or by viciouscustoms and corrupt habits […]. (Summa theologicaI-II, q. 94, a. 6, corp.)

A final problem seems to emerge: are we not, according toAquinas’s account of the erroneous conscience, left with thepossibility of a moral dilemma? For if we have an obligation to alwaysfollow our consciences, but we sometimes sin when we do follow them,then it seems that we are sometimes put into a double bind. We seem,that is, to sometimes have conflicting obligations so that regardlessof what we do, we sin. Aquinas’s solution is that it is onlywrong to follow a conscience that is in a state of vincible ignorance.Since such ignorance is by definition correctable, we can alwaysresolve the apparent dilemma by choosing to put aside our ignorance.As far as acting from invincible ignorance is concerned, we arepardoned.

3.3 William of Ockham: New Directions in the Understanding of Synderesis and Conscience

With the fourteenth-century theologian William of Ockham(1285–1347) we encounter some radically new developments on thetopics of synderesis and conscience. While Ockham’s Franciscanpredecessor John Duns Scotus had disagreements with Aquinas about thenature of the moral law, Scotus fundamentally agreed with theDominican in viewing synderesis and conscience a habit and an act ofthe practical reason, respectively, whose jobs were to apprehend thebasic principles of morality in the case of synderesis, and to applythem in the case of conscience (John Duns Scotus,Ordinatio2, d. 39; Wolter trans. 1997: 162–163). Like Scotus, Ockham alsoagrees with Aquinas in several crucial respects. Where Ockham departsfrom Aquinas, and indeed with the entire scholastic tradition whichpreceded him, however, is in his abandonment of the concept ofsynderesis, and in his unique approach to the invincibly erroneousconscience.

It is difficult to know for certain why Ockham abandoned the conceptof synderesis. Michael Baylor, however, has suggested twopossibilities. The first is that, as we have seen, synderesis wasregarded by Ockham’s predecessors, like Aquinas, as an inbornhabit. But for Ockham, rational agents only come to possess habits byacquiring them, and they can only acquire them by doing the relevantacts repeatedly. The notion that a habit could be innate, then, wouldhave seemed incoherent to Ockham (Baylor 1977: 78; Fuchs 1952:5–6).

The second possible explanation—though Baylor thinks thisimplausible—has to do with the way that Ockham understands thefoundations of morality as compared with Aquinas. For Ockham, there isno essential connection between the moral order as it currently existsand the divine wisdom. The highest norm of morality is the divinewill. It just so happens that murder, for example, is wrong today. Butthere is no reason that God could not make murder right tomorrow if heso willed. The moral order, in short, is contingent. On the Thomisticview, however, the natural law is a participation in the eternal law.It is the point of contact between God’s plan for us asconceived in the divine mind, on the one hand, and the humanintellect, on the other. Synderesis, as we saw above, plays a key rolein this connection insofar as it grasps the moral principles that leadhuman beings to their final destiny. Moreover, the moral principlesthat guide us in how to achieve our final end are as true today asthey were yesterday, and indeed will be for all time, owing to thenatures that God has bestowed upon us. As Baylor writes:

As the element of man’s original nature which was substantiallyundamaged after Adam’s fall, thesynteresis was theanthropological point of connection between an abiding moral order,which manifested ideas in the divine intellect according to whichcreation was necessarily ordered, and man’s certain knowledge ofuniversal principles of that moral order. Ockham, however, stressedthe absolute contingency of creation […] For Ockham,God’s will, as manifested in the moral precepts he has ordained,constitutes the ultimate and objective norm of morality. God is underno obligation; rather, it is divine will which determines moralobligation. This awesome conception of divine liberty and omnipotence,and the contingency of the created order has led many to theconclusion that the objective basis of Ockham’s ethics isauthoritarian or positivistic and inherently unstable since it appearsto depend only upon an alterable divine fiat. If this were so, then itwould appear odd also to posit within man an inborn and inalienableknowledge of moral principles in the form ofsynteresis.(Baylor 1977: 79–80)

A distinguished proponent of the interpretation Baylor describes wasServais Pinckaers. Because the foundations of morality are rooted inthe divine will, which can change, there was no need for Ockham toresort to a mechanism that discovers the eternal principles ofmorality as these emerge from human nature since, for Ockham, no suchprinciples exist. Rather, according to Pinckaers’ interpretationof Ockham, moral principles are known through revelation. (Pinckaers1993: 258). While Pinckaers was correct in his assessment ofOckham’s metaethics—which is fundamentally authoritariandespite elements of rationalism—he was wrong in hischaracterization of Ockham’s moral epistemology. This isbecause, while it is indeed possible to come to know the principles ofmorality via divine revelation, on Ockham’s account, it is alsopossible, despite their grounding in God’s will, to come to knowthem via natural reason and experience (see Eardley 2013:82–87). Examples of the former, that is, of principles that areself-evidently true, are “every blameworthy evil is to beavoided” and “the will ought to conform itself to rightreason”. An example of a moral proposition that is grounded inexperience, on the other hand, is “an angry man should be calmedwith soothing words” (Eardley 2013: 86–87). God obviouslywills that we should follow such injunctions. But how can we know hiswill if not through revelation? Although the contemporary philosopherPeter Geach was not a particularly sympathetic reader of Ockham, hewas willing to concede the possibility that a metaethics grounded indivine commands could nonetheless yield a naturalistic moralepistemology. As he put it:

the rational recognition that a practice is generally undesirable andthat it is best for people on the whole not even to think of resortingto it is thus in fact a promulgation to a man of the Divine lawforbidding the practice, even if he does not realise that this is apromulgation of the Divine law, even if he does not believe there is aGod. (Geach 1981: 170)

Ockham would have agreed.

A second and related way in which Pinckaers misinterpretedOckham’s moral epistemology was Pinckaers’ assumptionthat, because Ockham discarded the traditional notion of synderesis,he must have done the same for its twin concept of conscience.Pinckaers conceded that moral principles, even if rooted in the divinewill, still need to be applied to particular situations onOckham’s account. This role was, of course, reserved forconscience in the earlier tradition. In Ockham, according toPinckaers, this role now became associated with practical reason andprudence (Pinckaers 1993: 259).

A closer reading of the textual evidence suggests that Ockham verymuch made use of the traditional concept of conscience. Indeed, muchof how he employed the concept was consistent with the tradition,especially as articulated by Aquinas. Ockham associates the dictatesof practical reason, for example, with judgements of conscience. He isalso emphatic in his belief that rational agents have an absoluteobligation to follow their consciences, which can be correct orerroneous (Quaestiones variae, q. 8, a. 1, OTh 8: 411). Aconscience is correct when it is in accord with right reason; it iserroneous when it is not. Finally, an erroneous conscience, forOckham, as with Aquinas, is either in a state ofvincible—voluntary and therefore culpable—ignorance, or ina state of invincible—or involuntary—ignorance. Whereconscience is in a state of vincible ignorance, we must do our best toset it aside. In all these cases Ockham follows the tradition, withone exception: that of the invincibly erroneous conscience (Eardley2013: 94–98), the state in which the agent finds himself withthe correct universal principles, but non-culpably errs with respectto his grasp of the circumstances in which he finds himself.

In what sense does Ockham depart from the tradition? For Ockham, theact of following an invincibly erroneous conscience is not merelyexcusable, as it was For Aquinas, but “virtuous andmeritorious”. Consider the following example from Ockham. Whilewalking down the street one day you pass a homeless person who asksyou for money. He appears to have a moral claim on you since youassent to the moral principle that “help is to be given to everyneedy person in extreme need lest he die”. Does he appear needy,and indeed desperate to you? Yes. Sizing him up, you determine that,although it is theoretically possible that he could be fraud, thisseems unlikely. For Ockham, you are obliged in this instance to followyour conscience, and indeed you do. It turns out, however, that thisapparent homeless person is in fact a very wealthy person who isimpersonating a beggar. For Ockham, in following your conscience, youare not merely excused or absolved of your error, but your (ignorant)act is virtuous and, indeed, regarded by God as meritorious (so long,that is, that your act of charity is done out of love for God). AsOckham puts it:

Consequently, [in the above case] a right act of the will and an errorof the intellect remain at the same time with respect to the sameobject. And the whole reason is because that error is not in the powerof the one who is mistaken, who took all due diligence to find out thetruth, and therefore that error excuses from every sin. Andconsequently, the will that elicits the act in conformity to such[invincibly] erroneous reason acts virtuously and meritoriously.Indeed, had he not, while in such error, willed to help that person,he would have performed a vicious and demeritorious act because suchan act would have been knowingly elicited against conscience andagainst non-culpable reason, because in the aforementioned case hedoes not know that he is in error but believes that he possesses rightreason, and consequently by despising reason [in this way] he sinsmortally. (Quaestiones varie q. 8, a. 2, Oth 8:423–424)

What is motivating Ockham’s novel suggestion? Even Aquinasadmitted that we have an obligation to follow our consciences, whetherright or erroneous. When we do not do so, according to Aquinas, wesin. Of course, when our consciences are in a state of voluntary orvincible ignorance we also have a duty to put aside our error,otherwise we sin. It is obviously not possible, however, to put erroraside in the case of invincible ignorance since such ignorance is bydefinition involuntary. Accordingly, for Aquinas, we are obliged tofollow such a conscience. Although we act wrongly, in such cases, weare, for Aquinas, excused on the grounds that we could not have knownbetter. To return to Aquinas’s example of inadvertently sleepingwith someone who is not your spouse: this might be excusable, forAquinas, but there is no possibility that such an act might beconsidered virtuous, much less meritorious. But for Ockham, if it isvicious and therefore punishablenot to follow an invinciblyerroneous conscience, then merely being excused for following it whenwe are under a moral obligation to do so would be an insufficientreward. Rather, it should logically follow that it is virtuous andtherefore meritorious.

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Other Internet Resources

• Langston, Douglas, “Medieval Theories of Conscience,”Stanford Encyclopedia of Philosophy (Winter 2020 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/win2020/entries/conscience-medieval/>. [This was the previous entry on Medieval Theories of Conscience in theStanford Encyclopedia of Philosophy — see theversion history.]
• Medieval Theories of Practical Reason, entry by Christopher Toner in theInternet Encyclopedia of Philosophy.

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