Whatever the reason, people went to a Truffaut film not in the way that audiences today turn out for whatever new indie director -- good or bad -- happens to be hot at the moment, but with a mix of eagerness and expectation and, there's no way of getting around it, love. "Truffaut's films are easy to love," says director Olivier Assayas in the documentary "Frangois Truffaut: Stolen Portraits," "because they seem to love the audience." It was this popular image of Truffaut -- the filmmaker as compassionate man -- that Steven Spielberg had in his head when he cast Truffaut in "Close Encounters of the Third Kind," the sort of man people look at and think, "He'll understand." When Truffaut gently smiles at an addled old Mexican man who has witnessed a fleet of brightly lit UFOs, the man's confusion seems to clear away, and he confides his vision: "The sun came out last night, and it sang to me."

There are entire areas of Truffaut's work that that view doesn't encompass. No one who wrote with the vitriol Truffaut did during his days as a film critic ("rise up against French cinema"; "smash the seats when faced with these revolting films"), who expressed the bitterness over his own upbringing that still feels so raw in "The 400 Blows" or who understood -- and even sympathized with -- the depths of reckless passion that was the subject of one of his greatest films, "The Story of Adhle H." (1975), could have been entirely benevolent. But at their most lyrical -- and Truffaut was one of the three or four most lyrical filmmakers the movies have given us -- Truffaut's films made you feel as if the sun were singing to you. You sense that in the first shot of his first film, the 1957 short "Les Mistons," as the camera, placed in front of Bernadette Lafont, follows her bicycling down a summer street. If the palpability of the sun on Lafont's skin, the breeze rippling her dress, the fractured light falling through the overhanging leaves didn't all feel so completely natural, you might suspect that Truffaut had found a way to convince nature herself to put on a show for him. At moments like this, lyricism seems to be Truffaut's natural language, as it does in a (somewhat calculated) trifle like "Stolen Kisses" (1968) when the camera glides over the Paris rooftops while Charles Trenet sings on the soundtrack, or even in moments in a film as bad as "Confidentially Yours" (1983), when he simply films Fanny Ardant walking down the street in a trench coat.

For Truffaut and his compatriots in the nouvelle vague, the ambition to capture a poeticized vision of life as it is lived was not so much a break with tradition as a way to resume the tradition, interrupted by war, of French films of the '30s. Seeing only stultification and decay in the glossy "quality" films that dominated the French industry in the '50s, Truffaut, Jean-Luc Godard, Eric Rohmer, Jacques Rivette (first as critics at Cahiers du Cinema and then as directors) celebrated the en plein air style of Jean Renoir, Jean Vigo and Reni Clair. (In "The 400 Blows," young Antoine even cleans his dirty hands on a window curtain, just as Michel Simon used one to wipe his muddy shoes in Renoir's "Boudu Saved From Drowning.") Truffaut might have been summing up the cri de coeur of the nouvelle vague when, introducing a festival of Renoir films in 1967, he said, "His work unfolded as if he devoted his most brilliant moments to fleeing from the masterpiece, to escape any notion of the definite and the fixed, so as to create a semi-improvisation, a deliberately unfinished 'open' work that each viewer can complete for himself, comment on as it suits him, approach from any side."

There may be no film masterpiece more suited to that description than "Jules and Jim." And there may be no other film whose every frame sings with freedom in the way this one does -- not just in the story of two best friends (Oskar Werner and Henri Serre) whose lives are brought to their highest peaks of joy and bitterest depths by their love for the magnificent and perhaps mad Catherine (Jeanne Moreau), who will live only by her own rules, but in the way the film moves from style to style, from mood to mood, as if only the freedom to reinvent itself from moment to moment could do justice to his characters' spirit. Truffaut uses jump cutting and freeze frames, songs and newsreel footage, isolating sections of the frame the way Griffith did; at one moment the camera takes flight and soars over the countryside (the way it will later soar over the ocean in "The Story of Adhle H.") as if the film's mounting sense of joy and its compulsive need for movement had burst forth. "Jules and Jim" is one of the pinnacles of poetic storytelling in the movies. Jean Renoir said the film made him "most fondly jealous," and yet, as with Truffaut's description of Renoir's films, it's a perfect film that agitates for life over perfection. Which is why people who love the film have always tended to talk about it as if it were something they have lived rather than watched. And why, each time you go back to it, part of you expects it to be different than you remember it, as if it were so alive it had rearranged itself to suit some new whim.

In her review of "Jules and Jim," Pauline Kael described the two men as "the kind of artists who grow up into something else ... the dedication to art of their youth becomes the civilizing influence in their lives." Truffaut himself has often been described along those lines, but less kindly ("the once-wild child" is how the critic Paul Coates accurately and somewhat meanly summed up the later Truffaut). The cliché of Truffaut's career is that he became the sort of bourgeois entertainer he decried as a young film critic. And, as with every cliché, there is some truth to that. Certainly the later films seem more the work of a pro going through the (often clumsy) motions than of a filmmaker seized by a personal compulsion. The amour fou of "The Woman Next Door" (1981) belongs more to the machinations of melodrama than to Truffaut's earlier explorations of where passion becomes madness. It looks especially bad next to "The Soft Skin" (1964), never particularly well regarded, and a film whose coldness makes it tough to warm to, but which is ripe for rediscovery. Made after "Jules and Jim," it is as ruthlessly constrained and airless as that film was exhilarating. This portrait of a successful intellectual publisher (Jean Desailly) who begins an affair with a young stewardess (Frangoise Dorlhac, the sister of Catherine Deneuve, who was to die three years later in a car crash) burrows unsparingly under the surface of bourgeois life, but with something more akin to self-loathing than superiority. In their fine new biography "Truffaut," Antoine de Baecque and Serge Toubiana suggest the director was dealing with his own infidelities and perhaps the experience was too painful, too close to home.

The most entertaining of his later films, "The Last Metro" (1980), the story of a theatrical troupe trying to carry on with its business in occupied France, is also the most suspect. Though the central character is a Jewish director in hiding, the film suggests an apologia for the French who carried on with life as if nothing untoward were happening. And the pleasant, inconsequential "Day for Night" (1973), in which Truffaut himself plays the director of a soapy melodrama, is an apologia for cinematic mediocrity. "It is as much trouble to make a bad film as a good one," Truffaut wrote in the 1975 essay "What Do Critics Dream About?" And perhaps Truffaut, who now knew firsthand the difficulty of making movies, saw "Day for Night" as penance for the hard line he had taken as a young critic. But that expression of solidarity with anyone who steps behind a camera cannot disguise the uncomfortable fact that the sort of movie deadwood Truffaut looks kindly on in "Day for Night" is what makes life hell for filmmakers like him and those he championed.

Besides, what was best about Truffaut as a critic was the hard line he took. Truffaut the critic has things to answer for, namely the blinkered hero-worshipping auteur theory, and the criticism collected in his essential "The Films in My Life" often reveals very bad judgments. But just as he wrote, "I am not interested in all those films that do not pulse," Truffaut was not interested in writing reviews that did not pulse. Heedlessly partisan, alternating between love letters and threats, Truffaut wrote with a passion for movies as a vital, breathing thing that can make the most well-reasoned criticism look wan. (One of the reasons that a smart critic like Anthony Lane never seems more than a witty and entertaining stylist is that he appears embarrassed at declaring his enthusiasms without employing the buffer of irony.)

It can be painful to watch Truffaut try to replicate the American genres he championed as a critic in films like his Hitchcock homage "The Bride Wore Black" (1968) or the appallingly crude screwball outing "Such a Gorgeous Kid Like Me" (1973); it calls to mind Kael's apt remark that he was a greater director than he allowed himself to be. Truffaut really managed to invoke an American genre successfully only once, in 1960's "Shoot the Piano Player," one of his fastest, most joyous and heartbreaking films, and then (as Godard did in "Breathless") only because he allowed himself to break free of film noir's genre constraints. That's not to say that there isn't enormous charm to be found in his entertainments, like the films that followed "The 400 Blows" in the Antoine Doinel cycle -- "Stolen Kisses," "Bed and Board" (1970) and, to a lesser extent, "Love on the Run" (1979). The character Jean-Pierre Liaud is playing in them is no longer the young Truffaut (the Antoine of "The 400 Blows" deserves the title of the Jerry Lewis comedy "The Delicate Delinquent," and the young man Antoine seemed destined to become is the one Liaud played in Godard's 1966 "Masculine-Feminine") but a bumbling comic everyman, and despite Truffaut's over-eagerness to please his audience, you'd have to be awfully grouchy to resist entirely their modest pleasures. His most successful comedy was the one that could have been the most precious and sentimental, "Small Change" (1976), a film whose ensemble cast is mostly schoolchildren. Its slip-ups -- occasional speechifying and moments when the kids have been directed to cartoon their responses -- don't diminish the glancing confidence of scenes like the one where a small boy cracks himself up while regaling his buddies with one of those nonsensical dirty jokes that kids revel in.

But it's "The Wild Child" (1970), one of the two masterpieces of the last half of Truffaut's career, that is the deepest of all of his examinations of the world of children. Based on the true story of an abandoned 11-year-old boy found in 1798 living in the woods of France as a wild animal, the film tells the story of the efforts of Dr. Jean Itard (beautifully played by Truffaut) to civilize the boy, whom he has named Victor (played, with equal beauty, by the young gypsy boy Jean-Pierre Cargol). There have been, over the years, some modish attempts to see in Itard's attempts to educate Victor Truffaut's defense of his own embourgoisement (in "Stolen Portraits" Truffaut's daughter Laura talks of seeing a Berkeley teacher encourage some high-school students to accept this interpretation). It's a dopey reading that ignores both the realities of the world Victor lived in (his only other fate would have been to be turned over to a home for "idiot" children) and Truffaut's own acknowledgement of the pain Victor's education causes both the boy and Itard. In this film, education equals love (the film's dedication to Jean-Pierre Lhaud reinforces that), and though neither comes without discipline, discipline does not preclude compassion. "The Wild Child" is not about accepting the ready-made roles and edicts of society, but about insisting that society's only moral authority comes from its ability to show justice. The film is shot in luminous black-and-white by Nestor Almendros, and it's frequent iris shots recall Griffith, as do the combination of its simplicity of means and depth of emotion.

The spirit of silent films is also present in the last masterpiece of Truffaut's career, "The Story of Adhle H." Another true story, this one of the youngest daughter of Victor Hugo who literally went mad with love for an English lieutenant she pursued to Montreal after he had romanced her, "The Story of Adhle H." recalls, in Isabelle Adjani's incandescent performance, a cunning version of the characters that Lillian Gish played in her films for director Victor Sjvstrvm and the magnesium flare Falconetti showed in Dreyer's "The Passion of Joan of Arc." (Falconetti, feeling as if she had given everything she had, never acted again, and Adjani has never equalled this performance.) Truffaut seems to be both outside of Adhle, studiously regarding her (literally in one scene, where he appears on the street as an officer she mistakes for her beloved) and inside her mad obsession. If we can imagine the characters of films talking to each other, then we can see Adhle as the perfect match for James Stewart's love-obsessed detective in "Vertigo." They have both reached the point of no return, and all we can do is watch them in fear and admiration. Without once denying Adhle's capacity for cruelty and deviousness (she nearly ruins the life of the man she is pursuing), Truffaut is on her side. To him, she's the representative muse of passion without limits, a Catherine who has crossed the line and left common sense behind. She is also perhaps the greatest example of Truffaut's capacity for compassion and for rigorous understanding. The kick of the movie, and its greatness, is that in Adhle's self-destruction lies her triumph, the realization of a love so perfect that the rest of the world, even the man who started her fire burning, is shut out. It is an image of triumph the film ends on: not the mad Adhle wandering the streets of Barbados in her black cape, a Bronte heroine transplanted to the tropics, but the young Adhle standing at the edge of the sea and quoting from her journal: "That a young girl shall walk over the sea, from the Old into the New World, to join her lover -- this, I shall accomplish." I choose to hear that line as Truffaut's parting words to us, the audience he had built all over the world, who had long ago become his paramours, just as his films had become his means of crossing the world's barriers.