Nicolau de Cusa

Nicholas of Cusa (1401–64)

Also called Nicolaus Cusanus, this German cardinal takes his distinguishing name from the city of his birth, Kues (or Cusa, in Latin), on the Moselle river between Koblenz and Trier. Nicholas was influenced by Albert the Great, Thomas Aquinas, Bonaventure, Ramon Llull, Ricoldo of Montecroce, Master Eckhart, Jean Gerson and Heimericus de Campo, as well as by more distant figures such as Plato, Aristotle, Proclus, Pseudo-Dionysius and John Scottus Eriugena. His eclectic system of thought pointed in the direction of a transition between the Middle Ages and the Renaissance. In his own day as in ours, Nicholas was most widely known for his early work De docta ignorantia (On Learned Ignorance). In it, he gives expression to his view that the human mind needs to discover its necessary ignorance of what the Divine Being is like, an ignorance that results from the infinite ontological and cognitive disproportion between Infinity itself (that is, God) and the finite human or angelic knower. Correlated with the doctrine of docta ignorantia is that of coincidentia oppositorum in deo, the coincidence of opposites in God. All things coincide in God in the sense that God, as undifferentiated being, is beyond all opposition, beyond all determination as this rather than that.

Nicholas is also known for his rudimentary cosmological speculation, his prefiguring of certain metaphysical and epistemological themes found later in Leibniz, Kant and Hegel, his ecclesiological teachings regarding the controversy over papal versus conciliar authority, his advocacy of a religious ecumenism of sorts, his interest in purely mathematical topics and his influence on the theologian Paul Tillich in the twentieth century. A striking tribute to Nicholas’ memory still stands today: the hospice for elderly, indigent men that he caused to be erected at Kues between 1452 and 1458 and that he both endowed financially and invested with his personal library. This small but splendid library, unravaged by the intervening wars and consisting of some three hundred volumes, includes manuscripts written in Nicholas’ own hand.

1 Biography

Of Nicholas’ early life, little is known. He was one of four children born to Johan Krebs and Katharina Roemer Krebs. Still unconfirmed is the speculation that his father, a successful ferryman and hauler of merchandise up and down the Moselle, sent him to Deventer in Holland for part of his primary education. As for higher learning, Nicholas studied the liberal arts at the University of Heidelberg during 1416–7. Subsequently, he transferred to the University of Padua, where he came under the influence of the Italian humanists and acquired familiarity with the latest physical and mathematical theories. At Padua he studied principally canon law, receiving his doctor decretorum in 1423. In the spring of 1425 he continued his study of canon law at the University of Cologne where, apparently, he also gave lectures and where Heimericus de Campo introduced him to the ideas of Ramon Llull and Pseudo-Dionysius. In 1425 and 1426 he held benefices from the archbishopric of Trier, and by 1427 he was secretary to the archbishop himself, Otto von Ziegenhain. In 1428 and again in 1435 he was offered a chair in canon law at the University of Louvain, but on both occasions he declined, preferring to continue with his canonical and administrative work on behalf of the archdiocese and – at the Council of Basel – with his work as a member of the Council’s committee on matters of faith.

During his ‘Basel period’ (1432–8, not all of which time he was in Basel) he wrote, among other things, De communione sub utraque specie (On Communion Using Both the Bread and the Wine), against the Hussites, in 1433; De concordantia catholica (The Catholic Concordance) in 1433 and De auctoritate praesidendi in concilio generali (On Presidential Authority in a General Council) in 1434, both of which concern the demarcation of papal authority; and De reparatione kalendarii (On Amending the Calendar) in 1436, a proposal for revising the Julian calendar. At Basel he met John of Torquemada, whose treatise against the Muslims, Tractatus contra principales errores perfidi Machometi (Tractate Against the Principal Errors of the Infidel Muhammad) (1459), was to influence his own Cribratio Alkorani (A Scrutiny of the Qur’an) in 1461. Also affecting his response to the incursion of Islam into the West were his first-hand experiences of Islam in 1437, while present in Constantinople for two months (24 September–27 November). The delegation to which he belonged had been sent by the minority party of the Council of Basel to encourage both the Byzantine emperor and the Greek patriarch to reunite with the Roman patriarchate. It was on his return voyage from Constantinople, while still at sea, that Nicholas came to embrace the notion of learned ignorance.

Sometime between 1436 and 1440, Nicholas was ordained a priest. On 20 December 1448 he was named cardinal, and to him was assigned, on 3 January 1449, the titular church of St Peter ad Vincula in Rome. Some fifteen months thereafter (23 March 1450) he was designated bishop of Brixen in Tirol, where later his attempts to introduce monastic and diocesan reforms engendered enmity with Archduke Sigismund, whose threats forced him twice to flee to Rome. His death came on 11 August 1464 in Todi, Italy, as he was travelling from Rome to Ancona.

2 Two basic themes

The themes of docta ignorantia and coincidentia oppositorum were misunderstood by Nicholas’ contemporary and adversary John Wenck of Herrenberg, who in De ignota litteratura (On Unknown Learning) inveighed against Nicholas’ treatise De docta ignorantia (On Learned Ignorance). In a response, Apologia doctae ignorantiae (A Defence of Learned Ignorance), Nicholas made clear that the doctrine of learned ignorance is not intended to deny knowledge of the existence of God but only to deny all knowledge of God’s nature (except on the part of God himself). All our discourse about God is metaphorical; moreover, when we are conceiving positively of God, we are obliged to conceive of him in accordance with those metaphors that signify the highest perfections. The doctrine of docta ignorantia goes on to teach that the quiddities of created objects are unknowable by us precisely; that is, they are unknowable exactly as they are in themselves. Yet, although the objects are unknowable exactly in themselves, the objects themselves are not unknowable. Rather, they are apprehensible by us in coniectura, Nicholas’ expression for what is knowable only imperfectly and perspectivally. The doctrine of learned ignorance constitutes a radical break with the scholastic affirmation of a real, but remote, resemblance between God and his creation. The late scholastic William of Ockham had repudiated the validity of all alleged analogical knowledge of God’s nature, though he nonetheless maintained that the predicate ‘being’ is used univocally in discourse about divine being and created being. By contrast, Nicholas regards even ‘being’ as an equivocal and metaphorical predicate when used of God.

The doctrine of coincidentia does not mean, as in John Wenck’s construal of it, that the universe coincides with God, nor does it serve to contravene the Aristotelian principle of non-contradiction within the legitimate domain of that principle’s application – that is, its application to the realm of finite affairs. All things are present in God ontologically prior to their creation, as illustrated by an effect’s being present in the priority of its cause. But just as, in its cause, an effect is the cause, so in God all things are God rather than being their differentiated, finite selves. Nicholas nowhere teaches, unqualifiedly, that all things are God; indeed, he expressly rejects pantheism and its variants. Though he speaks of God as not other than (non aliud a) the universe, he does not mean that God is identical with (non aliud quam) the universe, but rather that God transcends the domain of comparison with all finite objects.

3 Ontology

Nicholas’ ontology has been interpreted along two very different lines. According to one line of interpretation, Nicholas regards finite objects as having no respective positive essence of their own, for God himself is the self-identical essence of each finite thing. Accordingly, the relative identity of each thing is said to consist only in its difference from all other finite things, all such differences being accidental and all relations between these things being internal relations. Thus in this view, propounded in Europe by Heinrich Rombach (1965) and in North America by Thomas P. McTighe (1964), created things are not substances and do not differ from one another substantially. According to the second, more generally accepted line of interpretation – one taking its lead from Nicholas’ Apologia – some created things are substances, and these do have positive essences of their own. In accordance with their respective essences, finite things differ essentially from one another. God is the Essence of these things in that he is the Essence of the respective essences of these things, even as he is being itself (entitas), which sustains in existence whatever is a being (ens). This distinction between being and beings Nicholas draws from Meister Eckhart; and it is one of the distinctions that influence both Paul Tillich and Martin Heidegger.

In De filiatione Dei (On Being a Son of God) 3, Nicholas’ likening of all created beings to mirrors that mutually reflect one another prefigures Leibniz’s systematic use of a similar theme (see Leibniz, G.W.). Also parallel with tenets in Leibniz are the assertions (1) that each kind of thing – though not each individual within that kind – is as perfect as that kind of thing can be and (2) that physical objects (which, for Leibniz, are ‘well-founded appearances’) are, in principle, infinitely divisible. Nicholas’ various utterances regarding nihil (not-being) in relation to esse (being) have struck some interpreters as inchoately Hegelian, in a dialectical sense (see Hegelianism). Others have seen Nicholas not as working with logico-ontological categories but as being a metaphysical nominalist. In the last analysis, his theory of universals (if not his theory of transcendentals) must be reckoned to be a moderate realism that is cognate with that of Aristotle and Aquinas.

4 Cosmology

At times Nicholas denies that the universe is finite and also denies that it is infinite; at other times he asserts that it is both finite and infinite. It is not finite, he tells us, in that it is not physically limited by anything outside its dimensions; on the other hand, it is finite in that it has a definite measure, known to God alone. In other words, the universe is finite but unbounded; yet, Nicholas terms it privatively infinite, in contradistinction to God, who is negatively infinite, since he is not even conceivably limited.

Because there is no perfect precision in the world, explains Nicholas, the universe’s circumference is not perfectly spherical, nor is the earth a perfect sphere. Consequently, neither the universe nor the earth has an exact physical centre and, thus, the earth is not the fixed centre of the universe. Indeed, the earth is not stationary but, like all stars and planets, has a circular movement of its own, though this movement is undetectable by us, its inhabitants. Likewise, the earth appears to us to be at the centre of the universe, and we infer that the ‘fixed’ stars are at the outer circumference. However, these stars also have inhabitants, who will judge themselves to be at the centre and the earth to be on the periphery. Furthermore, both the earth and the moon, as also the other heavenly bodies, emit a light and a heat of their own, even though both the earth and its moon also reflect the sun’s light and heat. Nicholas’ cosmological claims do not anticipate those of Copernicus, but they do deviate in important respects from those of Aristotle and Ptolemy.

5 Epistemology

In De visione Dei (The Vision of God) 24, Nicholas states that ‘there cannot be in the intellect anything which is such that it was not first in the senses’, thus rejecting the notion of innate concepts. Yet, in Idiota de mente (The Layman on the Mind) and elsewhere, he allows that the mind, through construction, can make concepts of things (such as a spoon) whose forms are not found in nature. Moreover, the mind has an innate power of judgment (vis iudiciaria) by which to weigh the strength of rational considerations and through which it is familiar, a priori, with basic moral principles (Compendium 10). Although human beings cannot know the exact quiddity of any given thing, they do nevertheless perceive the things themselves, through the medium of sensory images and conceptual forms. In places, Nicholas emphasizes (1) sensory and conceptual perspectivity, (2) the role of reason (ratio) as synthesizer and (3) the conditioning operations of the intellect (intellectus). (One must be careful, however, not to exaggerate his dim prefiguring of Kant.) Mathematical knowledge he regards as a priori and certain, because mathematical entities are conceptual entities elicited from, and known in a precise way by, our reason (De possest (On Actualized-possibility) 43–4). In Idiota de mente 6 he seems to endorse the doctrine that these conceptual numbers are ‘images’, as it were, of God’s thought. The mathematical puzzle with which he is principally preoccupied is that of how to square the circle: in other words, how in a finite number of steps to construct, using only an unmarked straight-edge and a drawing compass, a square whose area is equivalent to that of a given circle.

6 Christology

Nicholas’ Christology is orthodox, inasmuch as he considers Jesus to be the incarnate second member of the Trinity, uniting in his divine person his divine nature with a human nature. In accordance with the divine nature, Jesus is the Absolute Maximum; in accordance with his human nature, he is the contracted maximum individual. The Absolute Maximum is Infinity itself and is such that nothing greater than it can be conceived; the contracted maximum is an individual creature that is of maximum perfection within its kind. (By ‘contracted’, Nicholas means restricted, differentiated or delimited, so as to be this thing and not that thing.) Thus Jesus’ human nature is the perfection of the possibility of human nature. Furthermore, since human nature, which consists of a body and a rational soul, is a middle nature – a nature in between the higher intelligible natures (namely, angels) and the lower corporeal natures (namely, brute animals and non-animate things) – Jesus’ perfect human nature is ‘the fullness of all the perfections of each and every thing’. Thus, reminiscent of Eriugena’s De divisione naturae, the perfect world that went forth from God in creation is reunited to God through the subsumption of Christ’s human nature in his divine nature.

7 Ecclesiology

In De concordantia catholica, Nicholas seeks to demarcate the respective authority of a universal council and of the pope. A universal council (in contrast to a patriarchal council) is one to which bishops and select ecclesiastics from all five patriarchates have been called – a call issued usually by a patriarch or a patriarchal council, or an agent of either. A universal council may depose a heretical pope. A decision (on matters of faith) reached with a high degree of agreement by a universal council is more trustworthy than would be a decision on such matters by the pope alone. Yet, on matters of faith, the pope’s consent as well as the council’s is required for declaring a decision infallible. Nicholas speaks of degrees of infallibility, and he relates these to degrees of consensus: the greater the consensus within a universal council and beween this council and the pope, the greater the infallibility of the decision reached. Nicholas later was to abandon his claim that the authority of a universal council in which there is substantial agreement is superior to the pope’s authority.

8 Ecumenism

The dialogue De pace fidei (On Peaceful Unity of Faith) serves to challenge the various leaders of the different religions to adopt religio una in rituum varietate, a common religion that admits of diverse rites. The spirit of this ‘ecumenism’ is reinforced in Cribratio Alkorani, where Nicholas seeks to find common ground between Christianity and Islam. Yet Nicholas’ is not a genuine ecumenism, for he aims to show how other religions can be led to discern the truth of the doctrines essential to Christianity while retaining many of their own diverse rituals and liturgies. Through his programme of learned ignorance, he envisions the possibility of worshipping a God who, as infinite, is neither trine nor one in any sense in which trineness and oneness are positively conceivable by us. By thus adapting Eckhart’s distinction between God and Godhead, Nicholas can regard the doctrine of the Trinity as no longer a stumbling block to Jews and Muslims.

9 Conclusion

Nicholas’ system of thought is often misapprehended, sometimes in a way that detracts from his real genius, sometimes in a way that is all too flattering of his intellectual accomplishments. A proper grasp of his ideas will locate him, no doubt, somewhere between the invective of John Wenck, who condemns him as a corrupter of Aristotelianism, and the praise of Heinrich Rombach, who sees him as a new Aristotle for the modern period, as someone whose anti-substantive, functionalist ontology is as revolutionary as was Aristotle’s introduction of hylomorphism in the first place.