What makes Eagleton’s intervention curious is that he is a Marxist. One might be forgiven for assuming he would be firmly on the side of the godless. Eagleton was, however, raised a Catholic, and, as his memoir, The Gatekeeper (2001), makes clear, he retains a strong sentimental attachment to his religion. Much of his recent work has been characterised by what he has called its ‘theological turn’. This turn has now advanced well beyond the stage where it might be remedied by a cup of tea and a good lie down. Eagleton has not quite arrived at the point where, like the religious figures he remembers from his childhood, he waves away doctrinal absurdities with the phrase ‘It’s all a mystery!’ But his attempts to establish the consanguinity of historical materialism and medieval theology – a heady combination, if ever there was one – have involved him in some vigorous intellectual contortions.

Eagleton’s precise theological views can be tricky to pin down. In Reason, Faith and Revolution, for example, he reserves particular scorn for the New Atheists’ assumption that the Christian God is some kind of paternal figure or supernatural agent or divine creator. Placing to one side the beliefs of millions of faithful, he argues that a deeper theological understanding reveals God to be no such thing. God is, rather, ‘the condition of possibility of any entity whatsoever’. He is incommensurate with the reality of human experience. He does not intervene in the workings of creation, nor can he become the object of human cognition. On Evil takes up the point. As an example of the kind of wisdom that is revealed when one is properly versed in the work of medieval theologians such as Thomas Aquinas and John Scottus Eriugena, it offers the view that God is, among other things, ‘pure vacuity’, ‘without point or purpose’, and ‘pure nothingness. He is not a material entity or an extraterrestrial object. He cannot be located either inside or outside the universe.’

Of course, if we accept what Eagleton calls the ‘orthodox’ theological view – namely, that God is an inhuman, inexplicable, intangible, unlocatable, unthinkable, pointless, non-creating, uncommunicative nonentity – then God’s relevance to human affairs would appear to be limited. Certainly, anyone who claims to speak on God’s behalf can be safely told to rack off. By definition, such a deity has no implications for questions of morality, value or meaning. It can have no objection to gay marriage, contraception or female priests; nor could it father a son or require any form of religious observance. Even attributing indifference to such an ineffable non-being would seem to be laying on the anthropomorphism a bit thick.

Consistent with this view, On Evil dismisses all forms of theodicy – that is, the attempt to reconcile the existence of purposeless suffering with the idea of a benevolent God – as ‘bogus’. Yet, as a number of responses to Reason, Faith and Revolution pointed out, Eagleton is happy to attribute positive human characteristics, such as aesthetic preferences and a capacity for love, to pure nothingness when it suits his argument. He describes God as an artist who ‘made the world’ and celebrates Jesus as a ‘cross between a hippie and guerilla fighter’, forgetting that orthodox theology, rather surprisingly, reduces Jesus to the status of an ill-fated moral philosopher. God, it seems, is sometimes an impure nothingness.

This basic equivocation is enabled, to some extent, by Eagleton’s idea of dialectical reasoning, which involves him bustling his argument in one direction, then scurrying back the other way, back and forth, back and forth, only to end up where he started, with his radical principles reaffirmed. The practical benefit of this method is that it allows him to try on a variety of not entirely compatible opinions and to take potshots at his enemies without necessarily claiming full ownership of the contrary view. But the endemic everything-and-nothing sophistry of his argument cannot disguise that its paradoxes are, in fact, common garden contradictions. Undaunted by the legend that Eriugena’s students stabbed him to death with their quills, Eagleton seems at times to regard his ability to have it both ways as a point of honour.

The immediate target of On Evil, and what seems to have particularly irked Eagleton about the New Atheists, is the liberal-humanist tendency to regard modern inventions, such as human rights and the smallpox vaccine, as evidence of progress. Such a view, he argues, overlooks the darkness and destruction that is no less a feature of modernity. It ignores what he proposes is the innate perversity of human nature, a radical and unbanishable capacity for badness and subversion that will always undermine utopian schemes. The concept of evil he presents as a chal-lenge to the kind of timid humanist who would be wary of the term’s metaphysical connotations and the absolute division it implies: ‘Either human actions are explicable, in which case they cannot be evil; or they are evil, in which case there is nothing more to be said about them.’

Eagleton’s contention is ‘that neither of these viewpoints is true’ – in other words, that evil is both real and explicable. On a certain level, this is unproblematic. One does not have to understand the concept as a form of religious mystification. The word ‘evil’ seems contentious, in part, because it admits of a mild ambiguity that is simple to avoid. This arises from the fact that the word is commonly used as a noun and not merely as an adjective. Thus, when we speak of evil it can sound as if we are talking about a thing, even though it is clearly an abstract noun, like love or freedom. Just as one can discuss love as an idea but cannot in reality separate it from the people who do the loving, it is not possible to identify evil as something that exists independently of its manifestations within a human context.

Indeed, the characterisation of any given action or thought as evil necessarily involves a moral judgement, which can only occur after the fact. Any such assessment must not only take into account real consequences but must also consider the complex questions of intention and motivation. This is why it makes no sense to describe a destructive non-human phenomenon, such as a tsunami or the Ebola virus, as evil. So while it is perfectly possible to think evil thoughts and commit evil deeds – as the likes of Pol Pot and Charles Manson have amply demonstrated – one makes an elementary blunder if one tries to extrapolate from this fact the existence of evil as some kind of palpable force or entity in its own right. Even if we take the term evil to describe only the most extreme examples of human wickedness, those atrocities whose excess and moral depravity seem to defy rational comprehension, the concept does not become transcendent. It remains stubbornly grounded in, and continuous with, the reality of human behaviour.

This is not quite Eagleton’s view. Though he argues that evil is a concept with its basis in reality, he is, in fact, attempting to juggle two different and ultimately incompatible arguments. The more modest version is a claim about human imperfectibility. On Evil develops what Eagleton calls a ‘materialist’ interpretation of the doctrine of Original Sin in parallel with a consideration of psychoanalytic theory, proposing that these are religious and secular ways of recognising the same basic truth: that, as Samuel Johnson understood no less than Sigmund Freud, our desires are never wholly satisfied by reality. Consequently, he suggests, we are not merely implicated in the moral complexities of our particular social context, but are also self-divided in a fundamental way that no amount of worldly amelioration can rectify. The proposition that we are flawed and compromised creatures prone to irrational, excessive and sometimes hateful behaviour is not, in itself, startling. Eagleton, however, goes further, positing a form of absolute evil, lacking in any practical purpose or legitimate object, expressing a total rage at the universe itself – an evil whose unqualified nihilism becomes ‘a form of transcendence’.

As a result, On Evil is an exercise in question-begging. If evil is indeed ‘a kind of cosmic sulking’, it requires the existence of a sulker, and sulkers are invariably finite beings with histories, psychologies and ideologies. Eagleton often personifies his subject as a way of fudging this point. ‘Evil,’ he asserts, ‘would prefer that there is nothing at all.’ Yet he offers no evidence that any person has ever preferred this. Nor does he establish that, if someone did think this way, the thought could be anything other than idle.

On Evil begins by recalling the terrible murder of the toddler James Bulger, who in 1995 was abducted and killed by two ten-year-old boys. Eagleton cites one of the policemen assigned to the case, who stated that as soon as he laid eyes on one of the killers he knew the boy was evil. This use of the term, Eagleton rightly points out, is ideological. Its purpose is to pre-emptively judge the boy’s guilt, to declare his moral badness absolute, to deny the possibility of understanding or sympathy by ruling out of bounds any appeal to mitigating circumstances.

The question On Evil conspicuously fails to answer is under what circumstances it becomes possible to apply the term – in the transcendent-rage-at-creation sense and not just as a way of condemning an unusually shocking crime – without it becoming ideological in this manner. It gives no indication of where and how evil might be identified in actuality, not just in the work of novelists with theological axes to grind, such as William Golding and Graham Greene. Scattered throughout are references to famously depraved criminals – Hitler, Stalin, the Moors murderers – but Eagleton tends to lapse into agnostic phrasing when it comes to the question of whether these are genuine examples of pointless, universe-negating evil. Hitler and Stalin committed evil deeds, but they also had worldly aims. And, as Eagleton remarks at one point, if someone like Stalin is not evil, then it is difficult to know who is. The September 11 hijackers, who not only committed mass murder but went willingly to their deaths because they believed they would be rewarded in heaven, would seem to have displayed the sweeping contempt for material existence that is symptomatic of evil. Yet, according to Eagleton, their actions were ‘wicked rather than evil’ because they can also be seen as having a political motivation.

At this point, Eagleton’s notion of absolute evil disappears into its own vacuity. Like his definition of God, it purchases metaphysical purity at the cost of irrelevance. As a category it is analytically useless, not simply because it ultimately describes nothing, but because it also explains nothing. There is a tacit admission of this in the book’s anticlimactic conclusion, in which Eagleton claims that true evil is very rare and not something we need to worry about. Having begun by chiding his fellow Marxists Perry Anderson and Fredric Jameson for failing to treat evil as a serious issue, he ends up conceding that we should look to institutional causes for bad behaviour. We can hardly do otherwise. Eagleton has, of late, taken to asserting that people who believe the world would be better off if there were a little more respect for human rights are utopian, while those who are calling for the overthrow of global capitalism are being truly realistic. Near the end of On Evil, he also claims with a straight face that we do not yet know the true moral character of humanity because it has not been observed ‘other than in desperately deformed conditions’. Such observations, whose naïveté is borderline delusional, are straight out of an undergraduate bull session. On Evil, for all its bluster, merely underscores the extent to which Eagleton’s political radicalism and his theology have deteriorated into a lot of waffling nonsense.