Groucho Marx’s well-known witticism ‘Why should I care about posterity? What’s posterity ever done for me?’ has a long history. Joseph Addison, in the early eighteenth century for instance, couches it as: ‘We are always doing something for posterity, but I would fain see posterity do something for us.’ And that somewhat cantankerous relationship with posterity occurs in a good many examples over time. Fears about posterity - its power, its judgments, its forgetfulness - are not new, though perhaps the level of present guilt is so. There has always been the view that posterity can take care of itself. After all, posterity has the last laugh. It usurps us. Why should we serve it? Statesmen and politicians worry about their legacy – how they will be written into history. The judgment of posterity in such cases often throws a lurid light back upon the present, indeed is of course, simply a camouflaged judgment by the present.

The two dictionary definitions of posterity point up contrasted ways of imagining the future. In one definition, posterity is the single stream of issue from one forebear, with a legalistic tinge. This is how wills are written. In the other, we find a broadcast inclusiveness: posterity is all human generations that come after us. There may be tension between these two imaginings. Posterity can be the most selfish or the most disinterested of ideas generated out of present conditions: ‘to secure the blessings of Liberty to ourselves and our posterity’ – the opening sentence of American constitution: ‘our’ posterity here is national: who did it include? Who are ‘we’? – white American males only, or all American citizens, and what of the slaves?

If we lived for ever there would be no posterity, so death is intrinsic to the concept. But it is also a way of thwarting death. Both individually and communally our lives persist into the future through posterity. Yet posterity is always ghostly, unimaginable. It is a bank in which we put provisions for an after-life of sorts. But we shall never be able to withdraw our savings. We cannot know posterity. It is more remote than progeny, a coming-after when we are not. It is more severe than children, more public than family.

Exactly for that reason it has been the resource of those who feel under-appreciated by their contemporaries. The nineteenth-century awkwardly prophetic writer Samuel Butler, for instance, remarks that if you write for posterity you are bound to be misunderstood in the present. In writing for posterity you may be writing solely for yourself. The notion of posterity justifies what is simply an ideolect. Your peers can’t challenge posterity. The artist, or the politician, can claim renown, delayed. So ‘posterity’ has been an important trope for poets since the Renaissance and in the Romantic period. It can be boast or defence.

Not marble nor the gilded monuments
Of princes shall outlive this powerful rhyme;
But you shall shine more bright in its contents
Than unswept stone, besmear’d with sluttish time.
When wasteful war shall statues overturn,
And broils root out the work of masonry,
Nor Mars his sword nor war’s quick fire shall burn
The living record of your memory.
‘Gainst death and all-oblivious enmity
Shall you pace forth; your praise shall still find room,
Even in the eyes of all posterity
That wear this world out to the ending doom.
So, till the judgment that yourself arise,
You live in this, and dwell in lovers’ eyes. (sonnet 55)

In this Shakespeare sonnet, posterity and poetry combine to keep the lover alive. She or he is not yet re-embodied, as at the last judgment, but re-made in the actual reading of these strong words: the beloved is recognised by future lovers and held in their gaze. Here posterity remains in the future, vouching for the excellence of the lover, but the experience is authentic because we have it now, in the moment of reading. Something yet more strange happens in Shelley’s imagination.

Poets are the hierophants of an unapprehended inspiration; the mirrors of the gigantic shadows which futurity casts upon the present; the words which express what they understand not; the trumpets which sing to battle, and feel not what they inspire; the influence which moved not, but moves. Poets are the unacknowledged legislators of the world.

Poets are not so much harbingers as sounding boards for the future. They are not knowingly in league with what is to come, but they realise it unwittingly in their work. This emphasis on the prophetic power of poetry also insists that it realises its prophecy in the present.

Not all poets figure posterity in this high guise. Wordsworth claimed that he delayed publication of his great poem ‘The Prelude’ until after his death in order to provide funds for his posterity – his children were to live on the proceeds of this freshly revealed masterpiece. Undoubtedly he had other reasons too, to do with the constant revising of the poem that accompanied his life, but the practical insistence on funding his progeny chimes well with one view of posterity: we are responsible for making provision for those who come after, whether they be our own offspring or not. Indeed, in much ecological argument now, that responsibility is emphasised.

Posterity in the work of present-day writers is often dire. It is the bleak authoritarian time and community of Margaret Atwood’s Handmaid’s Tale or, perhaps even more threatening, of a world destroyed and engineered in her Oryx and Crake. It is the post-catastrophe world of Doris Lessing’s Memoirs of a Survivor (though that work ends with a move into tender impossibility). It is also the liminal world where death and life, past and present and future, leak into each other in W.G.Sebald’s Austerlitz:

I feel more and more as if time did not exist at all, only various spaces interlocking according to the rules of a higher form of stereometry, between which the living and the dead can move back and forth as they like (p.261)

Or is it, rather, here, that there is no room for the future, so dense is the traffic between present and past? Sebald knows, who more profoundly, that the future cannot be descried, or described, that catastrophe is insidious in its oncoming and that the childlessness of the solitary survivor expresses the expunging of a people. In such circumstances, after the Holocaust, the thought of posterity and of future generations seems to provoke despair as often as it provides hope.

Will posterity be very different from us? Even if we continue to look alike we may not be alike. In ‘Heredity’ Thomas Hardy gives a voice to the family face:

I am the family face;
Flesh perishes, I live on,
Projecting trait and trace
Through time to times anon,
And leaping from place to place
Over oblivion.

But that face gives no assurance of recognition.  The conditions of life change life, yes. So people’s judgments and the forms of their desires are likely to change. But the passions of the infant surviving in each of us are recalcitrant to change. Those infantile passions may be our one kinship and continuity with posterity.

Posterity is a secular concept. It involves no transcendence, though it frequently includes the hope of improvement. In eschatological systems such as Marxism its role is to provide hope, as if wisdom may be further accrued after revolution. In evolutionary theory the power of the individual to produce progeny, with their promise of further diversification through generations, signals at once the continuance and change of particular species. Evolutionary theory does not allow us to look far into the future. The processes of change within a long environment – itself composed of so many competing needs and desires – are so multifactorial that there is no telling what the outcomes may be. There is no long plan, no arc of teleology. Looking back, indeed, as Darwin insists, what we see is the vanishing of species, the collapse of history. The opposite of posterity is extinction. And extinction is ordinary, as Darwin everywhere recognises:

of the species now living very few will transmit progeny of any kind to a far distant futurity; for the manner in which all organic beings are grouped, shows that the greater number of species of each genus, and all the species of many genera, have left no descendants, but have become utterly extinct. (p395)

In the current nightmares of the future, posterity is called in evidence against us. We have defiled, defaced, distorted, the resources current in the world. Posterity will hold us to account and condemn us – if posterity survives to do so. Posterity may do so. But posterity probably won’t think about us very much. It will be preoccupied with its own concerns, and will take for granted the conditions in which it finds itself. It will, after all, be the present. So I disagree with the frequently expressed view, that without hope for posterity life becomes bleak and society self-destructs.