At first glance they seem unlikely subjects for comparison - Flaubert, a paragon of artists for art's sake who vowed ''to write well is everything'' and often spent whole days in creative agonies, seeking the exact word to consummate a single polished sentence; and Byron, the self-styled ''citizen of the world'' whose art responded to his several environments, who wryly advised that ''the greatest object of life is Sensation.''
In fact, Flaubert and Byron resemble each other in all the essential ways, though their styles of life and eventual fates could hardly have been more dissimilar. In these two splendid collections of letters (and, in Byron's case, related writings), two of the 19th century's most vital and fascinating spirits come alive for us in a most remarkable way.
The Flaubert ''Letters'' completes the two-volume ''selection'' which scholar-translator Steegmuller has made from the nine-volume Pleiade edition (itself drawn from the thousands of Flaubert letters extant). The selection is graced by its editor's authoritative linking of commentary and explanatory notes. As in the first volume, we see Flaubert deeply, almost exclusively absorbed in matters of literary practice and theory - here he debates crucial questions with such eminences as Baudelaire, Turgenev, Henry James, Zola, the young Guy de Maupassant, Edmond and Jules Goncourt, and his old friend the poet Louis Bouilhet.
In this book there's no single set-piece quite as entertaining as Flaubert's ebullient descriptions (in Volume 1 of the letters) of his 1849-51 trip to Egypt and the Middle East. Instead, there is a complex and multifaceted portrayal of the artist in midcareer - his literary eminence assured following the trial of his masterpiece ''Madame Bovary'' ''for public indecency''; his life pared down to a persistent routine of solitude and endless work.
The first letters in Volume 2 concern the arduous composition of Flaubert's historical novel set in ancient Carthage, ''Salammbo'' (1862). He did indeed undertake another research trip - to Algeria, to try to ''visualize'' his re-created milieu. This time, however, Flaubert's lively curiosity seems undercut by the frequently expressed ''disgust with modern life'' which, he confessed, lay behind this novel.
At about this time, Flaubert became a member of the ''circle'' of Princess Mathilde Bonaparte (Napoleon's niece); but the expression of conventional flattery was alien to his ironical temperament - and this brief flirtation with the haute monde was quickly concluded. As Flaubert grew older, his contacts with the ''real world''' became limited to reactionary grumblings about ''humanity's irremediable wretchedness'' and the atrocities of contemporary political thinking.
Work continued on his acerbic ''novel about modern life,'' ''Sentimental Education'' (1869); another historical novel, ''The Temptation of St. Anthony'' (1874); and the opus conceived of as his ''Encyclopedia of Human Stupidity,'' ''Bouvard and Pecuchet'' (left unfinished at his death in 1880). None of his works were well received, and Flaubert's chief solace throughout these difficult years was his correspondence with the eminent and popular romancer George Sand (Aurore Dupin). She was his ''chere maitre''; he, to her, was ''my old troubadour.'' If he sometimes discounted her literary advice, Flaubert adored George Sand's urbanity and vitality.
His final years, characterized by ''financial stress and mental torment,'' make for grim reading. The deaths of his nearest and dearest; the disdain for his work throughout France, ''where pedantry and ignorance reign''; his sad recourse to seeking a government post or pension - such losses and indignities might make pathetic a lesser being than this supremely courageous figure. But Flaubert's integrity and sense of self-worth never left him: They are the qualities that place his correspondence among the finest work he ever did.
A different tone pervades the vivid prose everywhere rampant in Leslie Marchand's expert distillation from his recently completed 12-volume edition of Byron's ''Letters and Journals.'' If that complete edition is essential for Byron scholars, this selection seems to me no less a must for all public libraries and many general readers: It's a rich and effervescent self-portrait, unlike anything else I know of in English.
Byron's high spirits and mischievous humor, his matchless linguistic facility , his manifest ''love of liberty and . . . hatred of cant'' burst through even in his most casual effusions. Writing as a schoolboy from Trinity College, he confides his discovery that ''this place is the Devil, or at least his principal residence.'' Romancing one of his several mistresses, he recounts the vindictive exactions of ''my mathematical wife'' and her (even more exacting) relatives. Writing home of foreign lands, he tosses off marvelous impromptu descriptions of a public execution, or the havoc caused by a mad, runaway elephant.
He renders incisive judgments on his literary rivals and assails his English publisher with mocking lamentations about ''the prudery of the present day'' - especially in regard to the issuing of his masterly long poem ''Don Juan.'' He can flatter women magnificently (saying of his separation from a beloved ''I am as comfortless as a pilgrim with peas in his shoes'') - while elsewhere conceding he holds ''no very high opinion of the (female) sex.'' In his finest moments, heroically involved in the Greek war of independence against Turkey, he accepts the certain knowledge that he will not live to see this freedom (''never mind me - so that the Cause goes on'').
One wants to go on quoting, from Byron's iconoclastic views: on children (''I abominate the sight of them . . . (and) have always had the greatest respect for the character of 'Herod' ''); on marital fidelity (''I am all for morality now - and shall confine myself henceforward to the strictest adultery'').
Byron impresses us as an incomparable performer, throwing off brilliant sparks almost without effort, lighting up vast and colorful arenas of varied interest. Flaubert, by contrast, seems the patient and sedulous laborer, the monomaniacal aesthete who really did give up his life to become a great writer. The real point, though, is that each incarnates the power of human intellect to comprehend experience. Both have had a liberating influence on later generations of writers and readers alike; both are, for all their surface differences, heroic and enduring figures. In their letters, as presented in these two indispensable volumes, we see each's heroism and humanity more clearly and compellingly than ever before.