Through conscience and its related notion, synderesis, human beingsdiscern what is right and wrong. While there are many medieval viewsabout the nature of conscience, most views regard human beings ascapable of knowing in general what ought to be done and applying thisknowledge through conscience to particular decisions about action. Theability to act on the determinations of conscience is, moreover, tiedto the development of the moral virtues, which in turn refines thefunctions of conscience.

• 1. Background
• 2. Bonaventure
• 3. Aquinas
• 4. Scotus and Ockham
• Bibliography
• Academic Tools
• Other Internet Resources
• Related Entries

1. Background

There are significant discussions of conscience among the Stoics ifnot before. (Using a broad definition of conscience as a form of moralself-awareness, Richard Sorabji claims that the notion of consciencecan be found in the Fifth Century BCE playwrights as well as in thewritings of Plato and Aristotle. See chapters one and two of hisMoral Conscience Throughout the Ages.) Seneca the Youngerdiscusses conscience in hisEpistulae Morales (43, 97, 105)and attributes several qualities to it. St. Paul discusses consciencein various letters (I Corinthians; Romans; Hebrews; Timothy). Whateverthe influence of Seneca and St. Paul might be on subsequentdiscussions of conscience and synderesis, late medieval discussions ofconscience derive from Peter Lombard's presentation of the concepts ofconscience and synderesis in hisSentences. Lombard cites apassage from St. Jerome, interpreting Ezekiel's vision of four livingcreatures coming out of a cloud. Each creature was shaped like a man,but each had four faces: the front face was human; the right was thatof a lion; the left was that of an ox; and the back was that of aneagle (Ezekiel 1.4–14). Jerome identifies the human face asrepresenting the rational part of man, the lion as the emotional, theox as the appetitive, and the eagle as that “which the Greekscall synteresis: that spark of conscience which was not evenextinguished in the breast of Cain after he was turned out ofparadise, and by which we discern that we sin, when we are overcome bypleasures or frenzy and meanwhile are misled by an imitation ofreason.” Jerome's comment that synteresis (alternatively,synderesis) is never extinguished in human beings and his remarkselsewhere to the effect that wicked people do cease to have anyconscience led Lombard and subsequent thinkers to distinguishsynderesis from conscience. While it is unclear that Jerome meant todistinguish the two, the distinction plays a major role in latemedieval discussions of conscience.

In these discussions, constant reference was made to certain works byPlato and Aristotle. Neither Plato nor Aristotle explicitly mentionconscience, however. It is their discussions of the virtues, practicalwisdom, and weakness of will that form the critical backdrop tomedieval discussions of conscience. These discussions were heavilyinfluenced by Augustine's modification of these classical authors. Forexample, Augustine championed Plato's notion of the unity of thevirtues, but he argued that love of God provided the unity to them.Moreover, he claimed that what pagan authors regarded as virtues werein fact vices unless they were developed for the love of God.

Two distinct views about the relationship between conscience andsynderesis emerged in the late Middle Ages. The first view, avoluntaristic one, can be identified with Franciscan thinkers likeBonaventure. The second, most clearly expounded by Aquinas, is anintellectualistic view. Both seem to derive from Philip theChancellor's treatise on conscience. In his treatise, Philip chieflydiscusses synderesis, and at times he describes it as an unerringintellectual dispositional potentiality that provides general truthsto conscience for specific application. At other times, he describessynderesis as the desire for the good, and it is equated withemotional reactions when one follows evil instead of good. This latterdescription fits well with Bonaventure's views on synderesis andconscience.

2. Bonaventure

Bonaventure discusses both in hisCommentary on theSentences, Book II, distinction 39. He places conscience squarelywithin the rational faculty, specifying that it is part of practicalreason since it is connected to the performance of actions. It is thusalso connected to the will as well as the emotions. On the other hand,he places synderesis in the affective part of human beings, for heregards synderesis as that which stimulates us to the good.

Conscience is divided into two general parts by Bonaventure. The firstpart seems to be a power for discovering the truth of very generalpractical principles like “obey God,” “honor yourparents,” and “do not harm your neighbors.” Thispart of conscience is innate and unerring; it cannot be lost to anyperson, no matter how morally corrupt that person may become. Thesecond part of conscience involves the application of the very generalprinciples to situations that may be either general orparticular. This second part is also innate, but it can be mistakensince the very general principles of the first part may be misappliedthrough ignorance or faulty reasoning. The misapplication explains, toa certain extent, how conscience, oriented to good, can be involved inthe performance of evil actions. The distinction between the two partsof conscience also opens up the possibility for developing, throughexperience, practical principles of behavior not directly entailed bythe content of the synderesis. By generalizing on activities performedin accordance with the principles of the synderesis, one can formulatenew general principles not contained in the synderesis that can guidebehavior in a number of contexts. Conscience thus appears to be adynamic faculty for Bonaventure.

Bonaventure calls synderesis the “spark of conscience,”and he sees it as resting in the affective part of human beings. It isthe spark because, as the general drive to do good, synderesisprovides the movement that conscience needs to operate. In general,Bonaventure regards conscience and synderesis as interpenetrating oneanother. The formation of ethical rules by conscience is seen by himas an implementation of a human being's desire for good (thesynderesis). He also sees the following of these principles as anotheraspect of the desire for good. Because we naturally have a desire forthe good, we also desire the means to that goal. The principles ofconscience are such means, and so we are naturally disposed to carryout the principles of conscience. Similarly, the emotional reaction todoing evil (guilt or remorse) is a reaction to the frustration of thedesire for good caused when one fails to adhere to what the consciencehas determined will lead to good. Bonaventure, while placingsynderesis and conscience in different parts of a human being, doesnot isolate them. On the contrary, he views conscience as driven bysynderesis and at the same time directing synderesis.

3. Aquinas

Thomas Aquinas, the principal advocate of the intellectualistic viewof the relationship of conscience and synderesis, explicitly defines‘conscience’ as the “application of knowledge toactivity” (Summa Theologiae, I-II, I) The knowledge hehas in mind here comes from the synderesis, which he regards as thenatural disposition of the human mind by which we apprehend withoutinquiry the basic principles of behavior. For Aquinas, then, theconscience applies the first principles of the synderesis toparticular situations. The principles of synderesis are rather generalin form. Examples are “Do good and avoid evil” and“Obey God.” To be helpful in human activity, consciencerequires principles that contain much more content. One can call these“secondary principles” and Aquinas discusses them inseveral places and suggests that they are derived from experience andinstruction through the virtue of prudence. Thus, the function ofconscience for Aquinas is to apply the general principles ofsynderesis and the more content-laden secondary principles developedfrom prudence to particular circumstances. Prudence is involved in theapplication to particular circumstances, according to Aquinas, becauseit is connected to the correct perception of individualcircumstances. And this aspect of prudence connects both conscienceand prudence to the problem of weakness of will.

In Aquinas's presentation of Aristotle's discussion of weakness ofwill in his Commentary on theNicomachean Ethics, the fourthposition offered in Book 7, Chapter 3 of theNicomacheanEthics is emphasized. According to this position, the incontinentman knows the appropriate general principles of behavior concerningwhat should be done, e.g., one should not fornicate. If theincontinent man sees a particular action as falling under this generalprinciple, e.g., a man sees that having intercourse with an unmarriedwoman is a case of fornication, he will not perform theaction. However, the incontinent man also holds the general rule thatpleasures should be enjoyed. If the incontinent man, driven by hisparticular desire for a particular unmarried woman, sees the proposedsexual liaison as a case of pleasure, he subsumes it under the generalrule about pursuing pleasure and pursues the relationship. The desirehe has, as it were, blinds him to the general principle aboutfornication he still possesses, but only habitually. The actualknowledge he possesses is that the proposed liaison is a case ofpleasure to be pursued. He thus has (habitually) the knowledge that heshould avoid fornication, but he fornicates nonetheless because heactually sees the fornication as an act of pleasure to be pursued. Asa general comment on Aristotle's analysis, Aquinas remarks: “It is notthe knowledge of the universal but only the evaluation of thesensible, which is not so excellent, that is dragged about bypassion.” (Commentary on the Nicomachean Ethics, Book 7,lecture 3, paragraph 1352) The point Aquinas is making is that theincontinent man possesses the knowledge of what he should do, but heis driven by the passion he has for a particular; this passion leadshim to act contrary to what the knows (habitually) should not bedone. The incontinent man so fails because he has failed to cultivatethe appropriate virtues that would enable him to size up the situationcorrectly (synesis) and deliberate well about it(eubulia). This analysis of weakness of will falls in linewith Aquinas's general view of the will as a passive potency thatalways follows the judgments of the intellect. While this view of thewill is modified by such disciples of Aquinas as Giles of Rome,perhaps under the impetus of the Condemnations of 1277, Aquinas'slinking of conscience with prudence and the virtues in general throughhis concern with weakness of will is innovative and undoubtedlyconnected with his interest in theNicomachean Ethics. DunsScotus and William of Ockham follow his lead in linking consciencewith issues surrounding development of the virtues.

4. Scotus and Ockham

Scotus offers very little explicit discussion of either conscience orsynderesis. Yet, from his discussion of issues chiefly concerned withdevelopment of the virtues, it is apparent that his view of conscienceand synderesis seems to draw from both Bonaventure and Aquinas.Following Aquinas, Scotus thinks that both synderesis and conscienceare to be placed in the intellectual order. In agreement withBonaventure, Scotus gives conscience much more of a dynamic role inthe human personality than a mechanical application of generalprinciples. Scotus's close linking of conscience and the developmentof the virtues allows him to combine the two sources.

According to the virtue tradition, in order to perform a virtuousaction, one must have the right dictates associated with the relevantvirtue. Yet, one must perform appropriate virtuous actions to developthe habit of the virtue and to know the relevant right dictates. Theobvious circularity seems vicious enough to undermine any attempt tocultivate virtues. Scotus regards conscience as offering a way intothe circle. Whenever a person formulates what is to be done in somecircumstance, this is an exercise of conscience, which has determinedproper action from the principles of synderesis. On the basis of thedictates of conscience, a person can perform an action that willprovide the basis for the development of the relevant virtues. For theperformance of these acts from conscience leads to the type of habitthat Scotus thinks of as a virtue. Ideally, the moral virtues areunified since a perfect, virtuous person should possess allvirtues. In fact, Scotus's perfect, virtuous person seems very similarto Aristotle's man of practical wisdom. This is the person who has,through long experience, developed the moral virtues and is able todeliberate so well about all moral situations that in Aristotle's viewto be moral is to do what a man of practical wisdom would do. Scotus'sperfect, virtuous person, like the man of practical wisdom, is skilledat determining what should be done in given circumstances; he takesdelight in acting in accord with his virtues, and he possesses all ofthe moral virtues by developing them through experience.

Ockham's discussion of conscience, prudence, and the virtues indicatesthat he follows Scotus's turn towards discussing conscience inrelation to the virtues. He agrees with Scotus that conscience canprovide the entry into the seeming circularity of performing virtuousactions in order to develop intentions that seem to be required forperforming the virtuous actions in the first place. Nevertheless, hecriticizes Scotus for failing to make a number of necessarydistinctions about degrees of virtues and the relationship ofconscience to prudence. He never mentions synderesis in his writingsand emphasizes the fact that only internal acts have moral worth.According to him, external acts are morally significant only byextrinsic denomination from internal acts. Particularly in these lasttwo claims, Ockham exercised considerable influence on Reformationthinkers like Luther and Calvin in their discussions of conscience. Infact, the topics of conscience and synderesis were discussed in Germanuniversities with great attention both before and after theReformation. Some of the thinkers involved in these discussions(Usingen and Peyligk) adhered in various ways to the views ofBonaventure, Aquinas, Scotus, and Ockham while others (Bernhardi andMelanchthon) blended and transformed the various views found amongthese thinkers. Many of these discussions related conscience toissues about practical reasoning. Interestingly, discussions ofconscience and synderesis appeared in works on naturalphilosophy. After Luther, the linking of conscience with practicalknowledge found in the writings of Aquinas, Scotus, and Ockham givesway, under the influence of Joseph Butler and Immanuel Kant, toconceiving of conscience as a faculty.

Bibliography

• Baylor, Michael G., 1977,Action and Person: Conscience in LateScholasticism and the Young Luther, Studies in Medieval andReformation Thought, Volume XX, Leiden: E. J. Brill.
• D'Arcy, Eric, 1961,Conscience and Its Right toFreedom, New York and London: Sheed and Ward.
• Davies, Brian, 1992,The Thought of ThomasAquinas, Oxford: Clarendon Press.
• Dolan, Joseph V., 1971, “Conscience in the CatholicTheological Tradition,” in William C. Bier(ed.),Conscience: Its Freedom and Limitations, New York:Fordham University Press.
• Eardley, P. S., 2003, “Thomas Aquinas and Giles of Rome onthe Will,”Review of Metaphysics, 56 (4): 835–862.
• Forschner, Maximilian, 2004, “Stoische Oikeiosislehre undmittelalterliche Theorie des Gewissens,” in J. Szaif andM. Lutz-Bachmann (eds.),Was ist das fur den Menschen Gute?/WhatIs Good for a Human Being?, Berlin and New York: Walter deGruyter.
• Holopainen, Taina M., 1991,William Ockham's Theory of theFoundations of Ethics, Helsinki: Luther-Agricola-Society.
• Iozzio, Mary Jo, 2006, “Odon Lottin, OSB (1880–1965)and the renewal of Agent-Centered Moral Thought,”ModernSchoolman, 84 (1): 1–16.
• Karkkainen, Pekka, 2012, “Synderesis in Late MedievalPhilosophy and the Wittenberg Reforms,”British Journal forthe History of Philosophy, 20 (5): 881–901.
• Kent, Bonnie, 1989, “Transitory Vice: Thomas Aquinas onIncontinence,”The Journal of the History ofPhilosophy, 27 (2): 199–223.
• Kent, Bonnie, 1995,Virtues of the Will. The Transformation ofEthics in the Late Thirteenth Century, Washington, D.C.:Catholic University of America Press.
• Kreis, Douglas, 2002, “Origen, Plato, and Conscience(Synderesis) in Jerome's Ezekiel Commentary.”Traditio,57: 67–83.
• Langston, Douglas C., 2001,Conscience and Other Virtues. FromBonaventure to MacIntyre, University Park: Pennsylvania StateUniversity Press.
• –––, 1993, “The Spark of Conscience:Bonaventure's View of Conscience and Synderesis,”FranciscanStudies, 53: 79–95.
• –––, 2008, “The Aristotelian Background toScotus's Rejection of the Necessary Connection of Prudence and theMoral Virtues,”Franciscan Studies, 66: 317–336.
• Lottin, O., 1957 [1948],Psychologie et morale aux XIIe et XIIIesiecles, Volumes I (second edition) and II, Gembloux:J. Duculot.
• Nelson, Dan, 1988,The Priority of Prudence, CollegePark: Penn State Press.
• Potts Timothy C., 1980,Conscience in MedievalPhilosophy, Cambridge: Cambridge University Press.
• –––, 1982, “Conscience,” inN. Kretzmann, A. Kenny, and J. Pinborg (eds.),.The CambridgeHistory of Later Medieval Philosophy, Cambridge: CambridgeUniversity Press.
• Saarinen, Risto, 1994,Weakness of the Will in MedievalThought From Augustine to Buridan, Leiden: E. J. Brill.
• Sorabji, Richard, 2014,Moral Conscience Throughout The Ages:Fifth Century BCE to the Present, Chicago: University of ChicagoPress.
• Zachman, Randall C., 1993,The Assurance of Faith. Consciencein the Theology of Martin Luther and John Calvin, Minneapolis:Augusburg Fortress Press.

Academic Tools

	How to cite this entry.
	Preview the PDF version of this entry at theFriends of the SEP Society.
	Look up this entry topic at theInternet Philosophy Ontology Project (InPhO).
	Enhanced bibliography for this entryatPhilPapers, with links to its database.

Other Internet Resources

[Please contact the author with suggestions.]

Related Entries

Aquinas, Saint Thomas |Aristotle, General Topics: ethics |Augustine, Saint |Bonaventure, Saint |Duns Scotus, John |Ockham [Occam], William |Plato |practical reason: medieval theories of | virtue: medieval theories of