In a pervasive modern view, which seems to most people so obviously true that they can think in no other way, the past is a burden that must be shed in order that a new kind of life can come into being. Modern human beings are always in transit to another place, which seems only more distant the longer they have been travelling.

It is a view of things that has a comical side, as Francis O’Gorman points out:

A concern with the multiple shapes of futurity situates us all in a joke, we might say, that has yet to conclude. Contemporary habits of mind are, in these terms, a gag without a last line, a gag without a gag… The experience of contemporaneity is, to phrase it in these mercurial terms, of waiting to know, and never finding out, what the penguin did in the bar.

In the future-oriented way of life that O’Gorman describes, we are all in the position of Hamm in Samuel Beckett’s Endgame, who, when asked if he believes in the life to come, replies, “Mine was always that.”

A cultural historian and professor of English literature at Edinburgh who has focused particularly on Victorian sensibilities, O’Gorman believes that the systematic devaluation of the past began in earnest in the 19th century, though it goes much further back. Today, disparaging the past is a mark of intellectual respectability. Anyone who believes that history involves loss as well as gain is reactionary: “The preference among liberal intellectuals is for a new kind of Whig history – one where the past is to be surveyed primarily to expose its failings…”

In this by now thoroughly conventional perspective, the values and structures of the past are seen as “always categories of power, where anything that is dominant is, by definition, oppressive. The only exception is the dominance of liberal ideas themselves, which can, it is assumed, never be oppressive.” In the 18th and 19th centuries, Whig history meant history written as a story of continuing improvement. Today, it means history written as an exercise in reproach and accusation in which universal human evils are represented as being exclusively the products of Western power.

Giving voice to oppressed and marginalised groups – ethnic and sexual minorities, subalterns of empire – may be a necessary part of historical inquiry. Yet as practised today by many historians, retrieving these occluded identities seems to require that other identities – local, national and religious, for example – be critically demolished and then consigned to the memory hole. Forgetfulness of the past must be actively cultivated, so that a future may emerge in which human beings can shape their lives as they please. As David Rieff argues in his powerful critique of commemoration, In Praise of Forgetting: Historical Memory and Its Ironies (2016), there may be times when laying the past aside is necessary for human beings to be able to live peaceably with themselves.

The end result of a systematic devaluation of the past, however, is a condition of confusion not unlike that experienced by those who suffer from Alzheimer’s disease. As O’Gorman puts it, “We may be terrified of dementia because it is widespread and its effects catastrophic. But the fear arises also because we are half-conscious, as dutiful forward-facing citizens of modernity, that we figuratively have it already.” Rather than enabling human beings to fashion new identities, a willed collective amnesia leaves them with no identity at all.

Many forces have combined to create this condition. Acutely, O’Gorman identifies one of the sources of the modern narrative in early Christianity. Announcing itself as the bearer of “good news”, Christianity “splintered the conception of human life based on sustaining a localisable past… The new faith, which must have seemed first of all a new Middle Eastern cult of the son of Joseph the Carpenter, not only discouraged acts of devotion to what had happened long ago… but also explicitly reorientated its followers’ minds to the future.”

Here, O’Gorman elides the original teaching of Jesus, which continued the traditions of charismatic Judaism, with the universal religion invented by Paul and Augustine. Yet the point remains valid. Christianity has always included “instructive rites for rejecting history”, acts of confession and penitence that are supposed to erase yesterday’s sins.

A Christian narrative of redemption in which past evils and crimes could be nullified by a dramatic act of moral renovation has inspired many modern revolutionary movements. “Christianity began the process of moving us toward the future,” writes O’Gorman. “The French Revolution from 1789 to 1815 (which was, ironically enough, violently antagonistic to Christianity as belonging to the past) clinched secular expectations about the relative values of tomorrow and yesterday.” When they sacked churches and defaced graveyards, the Jacobins were re-enacting a Christian rite in which history could be stopped and purified of sin, then begun anew.

O’Gorman does not make the point, but the current fad for destroying statues (of Confederate generals in the US or imperial figures in the UK) is also a rite of penitence and purification. Yet history never does stop or begin anew. The French Revolution gave the world the Terror, the Napoleonic Wars and the restoration of monarchy. Similarly, destroying statues will not correct past or present wrongs, only polarise society and exacerbate social conflict. The iconoclasts perform the ritual to impress on themselves and the world their superior righteousness.

The modern narrative may be a hollowed-out version of a religious myth, but by itself religion cannot account for the prevailing collective amnesia. A continuous process of memory loss is integral to contemporary capitalism. As O’Gorman puts it:

Capitalist modernity’s breathless desire is to forget. It is to draw a veil over histories, cultural narratives from the past, artefacts and achievements bequeathed to us by predecessors, and identities shaped by time, in preference for unknown material and ideological prosperities allegedly to come.

Mobility, fluidity and ceaseless innovation are the ruling imperatives in the turbo­charged economy that shapes our lives. Any­one who is unduly attached to a particular place or occupation, or identifies themselves with a specific community, risks being left mouldering in a derelict zone that will soon be forgotten. In this environment, the ideal character is someone without any definite identity, a bundle of desires and perceptions that responds to fleeting opportunities without needing to fashion a coherent life story. In a world supposedly brimming with infinite possibility, infinite adaptability has to be the paramount virtue.

The modern West has not always been ruled by what O’Gorman calls “our enthralment to forgetfulness”. Even in Victorian times, there were influential “dissenters from the future”. William Morris and John Ruskin are easily mocked as epicures of nostalgia, and neither of them formulated any practicable alternative to the militant industrialism of their time. But when Morris, in News from Nowhere (1890), described “the great achievement of the 19th century” as “the production of measureless quantities of worthless makeshifts”, he showed he had an astute eye for the future.

The key word here is “makeshifts”. Morris understood that the modern dissociation from the past has the effect of making the present permanently provisional. As the process of change accelerates, the future to which all activity is directed becomes more indeterminate and eventually indefinable. Any clear idea of a destination fades away, and all that is left is a sensation of movement.

Nowadays, it is liberals who celebrate this advance into an unknown future. Already displaying the historical amnesia they seek to impose on others, they imagine that a society dedicated to deconstructing its past will be one of equality and harmony. But as O’Gorman notes, an early-20th-century devotee of deconstruction was more perceptive. Writing in his Manifesto of Futurism (1909), Filippo Tommaso Marinetti asked rhetorically: “Why should we look back, when what we want is to break down the mysterious doors of the Impossible? Time and space died yesterday. We already live in the absolute, because we have created eternal, omnipresent speed.”

Ten years later, Marinetti co-authored the Fascist Manifesto, the founding document of Mussolini’s movement. For someone who wanted to raze all museums and libraries and demolish Venice – and demanded the prohibition of pasta on the grounds that eating it sapped virility – fascism in practice was bound to be something of a disappointment. Yet at least it was a bold move forwards. Modernity for Marinetti was the violent pursuit of an ill-defined future, without being too fussed about those who were crushed in the onward march, and fascism embodied this impulse.

A blend of intellectual history, cultural criticism and autobiography, Forgetfulness is too rich in thought and insight to be summarised in any detail. This is not another leaden academic tome on the discontents of modernity. Instead, like O’Gorman’s earlier book Worrying: a Literary and Cultural History (2015), it is a meditation on the contemporary condition that will change how readers think of their lives. Writing in an engagingly light, almost conversational style, O’Gorman subverts the dominant world-view in which the present is meaningful only in relation to an increasingly elusive future. A book as acutely intelligent and as original as this is a rare gift of fortune. Read it and you will not easily forget what you have learned.

You will discover how O’Gorman’s interest in the deconstruction of historical memory was stirred when he visited Mycenae with his girlfriend and looked at what was advertised as the grave of Agamemnon. He tells us that no one in his West Midlands comprehensive had taught him classical Greek, let alone anything of Mycenaean culture, but the experience of standing “among graves of almost-forgotten origin, and with stories that no one can recollect any longer whether they are true”, started a process of reflection about how the memory culture of the ancient world differed from the modern regime of mandatory forgetting.

You will read of the stroke O’Gorman suffered in his kitchen in Oxford in 1998, from which he has fully recovered, “except, pointedly enough, for a weakened memory, and, strange to say, slightly altered handwriting”. You will learn how The Mill on the Floss “projects a culture’s breaking with the past… on to the local history of a disappointed young woman in love”; how in different ways both Freudian psychoanalysis and cognitive behavioural therapy view the past as “a scene of misfortune”; how the first roads, railways and stock markets produced a sense of accelerating time; how the serialisation of Dickens’s novels fed his readers’ desire for the future, and much else that is arresting and thought-stirring.

O’Gorman acknowledges that there is no cure for modern forgetfulness. Any reminder of past achievements can only be an obstacle to a society that defines itself by an image of the future. The Taliban-like destruction of ancient monuments in Mao’s Cultural Revolution was not an aberration, since China’s traditional culture was dismissed as a relic of oppression. A similar rejection of the past featured in many of the last century’s totalitarian regimes. Now the liberal West is in the midst of its own cultural revolution. In acrimonious debates about immigration and attacks on cultural appropriation in universities, Western history is being repudiated as a zone of crime and barbarism.

O’Gorman frames this development in terms of the rise of multiculturalism. Liberal opinion, he writes, has settled on a position that assumes:

that all cultures, the diversity of all ways of life, are equally acceptable and to be affirmed at all times… Multiculturalism assumes, though usually implicitly, that because each culture is entitled to respect or at least to be free from judgement, a plurality of cultures can coexist harmoniously in the same hosted space while retaining their identities. This concept of mutual-harmony-with-identity is sometimes joined in the minds of the most extreme liberal intellectuals with bolder arguments that “national” and “cultural identity” are myths, forms of false consciousness, or divisive ideological tools.

Against this background, O’Gorman concludes, there has been a “revival of intolerance and, in some cases, literally of fascism”, including “the direct affirmation of Nazi ideology recast in versions of White Supremacy”. But it is a hyperbolic form of liberalism that has left contemporary societies vulnerable to the resurgent far right. A Marinetti-like mentality has reappeared in the current generation of ultra-liberals, who display a contempt for traditions of toleration and free expression mirroring that which has always defined the far right.

Demolishing national and cultural identities makes moral and political sense if – and only if – the result will be better than the liberal societies that have actually existed. Yet these societies are highly fragile settlements, regularly disrupted by war and economic crisis. Today they are also threatened by an ideology that wages war on their past. Societies that repudiate their historic inheritance in this way leave themselves defenceless against the dark forces that are now re-emerging. As George Santayana might have put it were he alive today, those who deconstruct the past are condemned to repeat it.

Forgetfulness: Making the Modern Culture of Amnesia

Francis O’Gorman

Bloomsbury, 192pp, £14