Pope Benedict XVI's 2006 encyclical, Deus Caritas Est, has two clearly distinct parts. In the first it deals with the nature of love and of charity, the highest form of love; in the second it treats the charitable activity of the Church. Most of the commentaries have focused on the second part, which raises interesting questions about the relation of Church and state, charity and justice. But the first part also merits careful study, for the encyclical is not primarily concerned with ethical problems but rather with communicating a philosophical worldview in which the Church's ethical teaching concerning love, marriage, and sexuality is intelligible.
In a famous 1908 study of the theology of love in the Middle Ages, the French Jesuit Pierre Rousselot identified two basic approaches: the more self-centered and the more altruistic. Some medieval thinkers emphasized love as desire (amor concupiscentiae); others emphasized love as benevolence or friendship (amor benevolentiae or amor amicitiae). Rousselot did not find two clear-cut schools in the Middle Ages, but he did find two tendencies. Theologians heavily influenced by Aristotle, such as Thomas Aquinas, argued that creatures who are imperfect continually seek to perfect themselves by embracing what is congenial to their nature. Rousselot called this theory of love "physical in the sense of natural. The opposite theory, which emphasized self-forgetfulness and sacrifice, Rousselot called "ecstatic." He found it in certain writings of the Victorine and Cistercian schools and especially among the Franciscans (Alexander of Hales, Bonaventure, and Duns Scotus).
St. Thomas, though he exemplified the natural theory, was more successful than others in reconciling the two points of view. Taking his departure from Aristotle, he held that everything seeks its own good, but he added that God was the common good of the whole universe and that human beings, by their spiritual nature, were open to union with God. "Just because every creature belongs to God naturally by everything it is," wrote St. Thomas, "it follows that by the very movement of its nature a man or an angel must love God more than itself." Human beings, in particular, are made in the image of God and thus tend to the divine likeness as their own perfection. St. Thomas, then, while remaining fundamentally in the Aristotelian tradition, escaped the trap of egocentrism.
Some twenty years after Rousselot, the Swedish Lutheran theologian Anders Nygren gave a different analysis in his well-known book Agape and Eros. He agreed that there are two types of love: the self-seeking, which he called eros, and the self-giving, which he called agape. Holding that only agape was truly Christian love, he argued that such thinkers as Augustine and Pseudo-Dionysius, under the influence of Neoplatonism, had taken the wrong path. They improperly commingled the biblical idea of agape with the Greek philosophical idea that the soul was in quest of the divine as the supreme goal of its innate longing. Medieval theologians, therefore, mistakenly thought that God drew all things to himself by his infinite goodness. In Nygren's estimation, Augustine and the whole medieval tradition failed to grasp the true Christian idea of agape, which meant a totally free gift, unmotivated by any need or desire on the part of the recipient. For Nygren, we are faced by a clear choice between two types of love; no compromise or synthesis between eros and agape is possible.
Writing in France about 1939, Denis de Rougement, son of a Swiss Protestant pastor, also drew a sharp contrast between eros and agape. The idea of eros as a frenzy or divine delirium, he maintained, was characteristic of the mystery religions, Plato, and the Neoplatonists. Love as a dark passion continued to make its appearance in various forms of Manichaeanism and medieval legends such as that of Tristran and Isolde. Whereas eros seeks to escape from the flesh and flee into a world beyond, agape represents God's embrace of this world and is symbolized by the marriage of Christ and the Church. De Rougement, like Nygren, confronts us with a stark choice between eros and agape.
And yet, as Martin D'Arcy points out in his fine work The Mind and Heart of Love, Nygren and de Rougement have different conceptions of both eros and agape. De Rougement characterizes eros as an irrational passion that is always discontented with earthly and temporal existence; it moves the lover to a total surrender of self and absorption into the All. For Nygren, on the other hand, eros is an intellectual and possessive form of love. As for agape, de Rougement sees it as an affirmation of this world and an acceptance of human limitations, including human life in its concrete conditions. Nygren, on the other hand, sees agape as an act of sovereign...