Richard Holmes is never alone. He walks in the company of poets, he speaks to the dead, he hears echoes and sees shadows. For him, the past is not a foreign country, it is an infinitely tangible region of the mind whose topography has lured him for the past 30 years. The English critic and author of a superbly illuminating two-volume biography of Coleridge (Early Visions, 1989 and Darker Reflections, 1998) began his excavations of literary lives in the late 1960s with an essay on the 18th-century poet, Thomas Chatterton - and discovered his vocation as a biographer. "In `Chatterton' . . . I first glimpsed the people and the period in history which were to become most dazzlingly alive for me," he writes.
While still in his 20s, Holmes published a passionate, award-winning biography of Shelley (The Pursuit, 1974) followed by a series of historical essays and character sketches of the dramatis personae of French Romanticism, written while he lived in Paris in the early 1970s. London and Paris are the twin poles of the cultural world in which he is immersed: that of the late 18th and early 19th century, and the brilliant generations of writers and thinkers fired by the legacy of the Enlightenment, by the French Revolution and its aftermath.
In Footsteps (1985) Holmes turned his attention to the business of writing biography, teasing out questions of authenticity, motivation and the biographer's assumption of omniscience. Footsteps, as he writes in his latest book, Sidetracks, asked "how much does the biographer create the fiction of a past life, the projection of his or her own personality into a story which is dramatically convincing, even historically correct, but simply not the human truth as it happened?" Part autobiography, part biographical sketches, part essay, Footsteps beautifully captured the obsessive, solitary nature of the young Holmes's biographical quests - "the peculiar infatuation of the wandering scholar" - as he hiked through the Cevennes, retracing Robert Louis Stevenson's famous journey by donkey; immersed himself in the tumult of revolutionary Paris, as witnessed by Mary Wollstonecraft and Wordsworth; or wandered for four years through Italy, in pursuit of Shelley and his entourage.
ootsteps was a landmark which opened up the possibilities of biographical form, introducing playfully discursive and fictional techniques and a self-conscious reflexiveness that has since become as commonplace in biographical writing as it is in fiction. For Holmes, however, the purpose of this commentary on the art of biography - which could be called meta-biography - is not fuelled by formal or theoretical concerns. It is to communicate something of his passion, of "the vertiginous experience of biographical research", in the service of "the ideal of truth-telling". He is, after all, a "Romantic Biographer".
In Sidetracks, he looks back over all his biographical writing and introduces, in chronological order, scripts for radio plays, essays and short sketches that have appeared in literary journals and magazines over the years, some of which fed into his longer works. At first glance this volume appears to be a collection of leftovers scooped up by a writer who has undertaken painstaking research and is reluctant to let it go to waste. But there is a narrative underpinning this collection, an autobiographical thread which invites the reader to join the author on his time-travel. It is "a personal casebook", Holmes writes . . . "the fragmented tale of a single biographical quest, a 30-year journey in search of the perfect Romantic subject and the form to fit it."
The metaphor of the journey, quest or voyage is central to his work, epitomising for him "the Romantic predicament". Holmes travels hopefully and roams widely. If some of his enthusiasms take him down some obscure alleyways - into the lives of "minor" Victorian scholars and clerics, for example - the reader is happy to wait for him to re-emerge into the bright, sunlit squares of history, peopled by the ever-fascinating figures of John Stuart Mill, Mary Wollstonecraft and William Godwin, Shelley, Coleridge, Voltaire and Boswell. Holmes has the great gift of evocation; his use of language can be dazzlingly pictorial and he understands the need for the biographer to let us hear a voice and see a figure in the landscape. He tempers his scholarship with wit and with empathy - "the most powerful, the most necessary and the most deceptive of all biographical emotions".
Holmes is concerned to impose shape and form on his own life's work so far - he is now 55 - just as he does with his biographical subjects. Looking back, he traces a trajectory from his youthful attraction to the solitary figures of Romanticism, from Chatterton dying alone in his attic at the age of 18, or Gerard de Nerval haunting Parisian asylums and committing suicide.
From this early emphasis on the heroic self, on "solitude, dislocation, and isolation from a normal social world", Holmes moves into another aspect of Romanticism, the passionate identification with another person. "The mature happiness possible between two human beings and the circumstances that foster it or endanger it . . . now confirmed itself as a central part of my biographical quest." In his linking introductory pieces, he explicitly connects his new-found interest in "the Romantic couple" with his own late marriage to Rose Tremain, his companion on Parisian sojourns, whom he refers to as "the beloved novelist".
Biography and love become intertwining themes: he traced the influence of Harriet Taylor's love on the work of John Stuart Mill, which led him back to the relationship between Mary Wollstonecraft and William Godwin, which he describes in the 167-page essay, "The Feminist and the Philosopher".
Their relationship, which combined bracing intellectual companionship and passionate love, was Holmes writes, a significant turning point in the history of human affections, and "an experiment in living".
As he charts his growing fascination with the "the vast geography of the human heart", it is clear that Holmes's journey is a sentimental one - in the 18th century sense. For him, "the truth" of individual human life is always in the foreground, and to this extent he writes in the tradition of Boswell or Carlyle.
He is post-Freudian, but not post-Marxist or post-Darwinian. For him biography offers "a shapely doorway back into history", and can provide an ethical mirror by which we see ourselves. The economic and sociological forces of history leave him cold and he has no more interest in historiographical theory than he has in literary theory. In fact he celebrates the independence of the flourishing biographical genre from "the groves of academe". Yet his geniality is deceptive; while he writes with a full heart, he is no cosy belles-lettrist or hagiographer. He doesn't flinch from difficult issues, such as Coleridge's plagiarism or Voltaire's anti-Semitism. For all his empathy, heightened sensibility and passionate curiosity, he is an acutely perceptive, sometimes combative critic. His commentaries here on Wollstonecraft's brilliantly observed, confessional travel book, A Short Residence in Sweden, Norway and Denmark and on Godwin's frank memoir of her after her tragic death, Memoirs of the Author of the Rights of Woman, are rigorous and illuminating. He emphasises the originality of both texts, which, he argues, constituted a revolution in literary genres.
It comes as no surprise that the essay on the brief, fruitful intersection of these two late-18th century lives lies at the heart of Holmes's book. Theirs was, as he says, a meeting of "Imagination and Reason", a conjunction that he is ideally equipped to appreciate.
Helen Meany is an Irish Times arts journalist