There is one Terry Eagleton, and he is Mephistopheles. Forty years ago, when New Left Church came out, heretically announcing to the British intelligentsia and briefly radical students the coincidence of Marxism and Christianity, Eagleton looked like a case, in Philip Larkin's words, of "never such innocence again".
Confronted now with Eagleton's eighth book in 11 years, if one doesn't exactly find innocence, one finds his trademark qualities in abundance: impishness, prodigious breadth of reading, a poacher's disregard of boundaries and of "no trespassing" notices, sublime self-confidence, and an opening up of the heart to old allegiances as sudden as a blow to the chest.
Eagleton can display the seriousness of Alasdair MacIntyre, the mischievousness of Slavoj Zizeck, the commitment of Raymond Williams and the effrontery of Dorothy Parker. These are, you might say, hellishly strong attributes.
In this portly new book he yokes together, with typical heterogeneity, the history of metaphysics and the diagnostics of psychoanalysis. His purpose is to tax ethical theory with these inspectors until he has found a mode of moral conduct for our day.
To turn a sharp joke of his own back upon its author, he is apt at times to confuse being au fait with being a la mode, for his taxonomist in the book is the sacerdotal Methodist of Parisian preposterousness, Jacques Lacan.
But to say so is at once to convict oneself of the stereotypical Anglo-Saxon empiricism it is Eagleton's programme to disembody. Lacan provides him with a not-so-new trinity (holy ghost, father, son) of the imaginary, or the moral realm of sympathetic identification; the symbolic, the realm of institutionalised morality such as the law and the will of government; and the real, the hardest realm, where desire and longing bear up and go down against estrangement and death, the loss of solidarity and of love. Eagleton assigns his friends and antagonists to one or other of the three categories, and weighs dauntlessly in.
The rational sentimentalists of the 18th century - David Hume's civil affections and Adam Smith's moral sentiments - come off worst. Eagleton, in his drastic, foreshortened way, treats a formidable array of spokesmen as well as the two Scottish dominies, before deciding that their theory of natural benevolence proves helpless before the monster of Victorian capitalism.
Baruch Spinoza provides a natural refuge for all those who hope to rescue theism by identifying God with an impassive nature, and Eagleton, the sometime seminarian, is much attracted by the thought. But he deals too scantily with the mighty Sephardist's grand, bleak vision, using batty old Louis Althusser, of all people, as subtext. His real target in this section is Immanuel Kant, and in a fresh and racy essay, Eagleton configures a familiar Kant who invented the dutiful bourgeois for whom service to the law is perfect freedom.
In part three, "The Reign of the Real", Eagleton dresses himself in a drab Franciscan homespun - no stylishly white Dominican robes here in spite of a handsome tribute to Herbert McCabe - in order to commend to us the grace and necessity of heeding the agony of our desire for unity with the cosmos, for impersonal goodness, for unattainable fulfilment.
It's a tortured diction he writes at this point, in spite of the jokes, in spite also of the throngs of names dropped as Eagleton struggles to enlist the decidedly modish as well as crazily repellent Alain Badiou (he who speaks well, unspeakably, of Mao's Cultural Revolution) as moralist of the real. The shower of dropping names is not showing off, however, it is how Eagleton thinks. But as they fairly pour down, six or seven to a page in the last section, the result is to stall the reader's mind.
For this is a book about ethics with scarcely a single instance from quotidian life. It is a book about books, and even in the final section in which, in a characteristic trope, Eagleton twists Hannah Arendt's famous phrase into his own "the banality of goodness", he pays nothing like enough attention to good old banality and its everyday needfulness.
Perhaps we are reading the work of a man living too much in libraries. Certainly there isn't enough history - the history of absolute presuppositions, of the embedding of old ideas in the new, of the history of quarrel and riposte as between thinkers and thoughtless. He is piercingly wistful for the two worlds he has lost, perhaps not for good: the reciprocal possibilities of Christianity and of socialism.
Finally, it is this longing that makes the book so haunting. The part Eagleton plays best is not Mephisto so much as Caliban.
Trouble with Strangers: A Study of Ethics
By Terry Eagleton
360pp, £45.00 and £17.99
ISBN 9781405185738 and 85721
Published 19 September 2008