Some genres emerge from experimentation and contrivance; others are driven by or spun off from commercial imperatives; still others evolve from the simple confluence of artists and subjects. Street photography — and certainly the " New York school of postwar street photography, " which is being showcased through the works of one of its lesser-known masters, Louis Faurer, at the Addison Gallery through July 28 — is the ideal example of the latter. Nobody sat around and formulated street shooting in the abstract; nobody had to think very hard to apply the longstanding genre to the streets of New York; and even as the movement peaked, in the 1940s and ’50s, nobody was buying many of the pictures.

The street genre is the photographer’s honest response to urban life. A city’s crowded confusion, diversity of purpose, economic contrasts, ironic juxtapositions, and mélange of private moments in public places cry out for the containment, documentation, categorization, interpretation, and control the still camera affords. Candid photography can give definition to the jumbled riches of city life. Its cultural purpose is intuitive; its product — extracted, necessarily abstracted, bits of an overwhelming context — is art invented in the moment. So many subjects; so many opportunities to give voice to drowned-out statements; so much to look at.

Louis Faurer (1916-2001) seems to have worshipped the act of looking to the point that it becomes one of several motifs running through the 137 of his photographs on display in Andover. Again and again, from the exhibit’s first photograph (and one of Faurer’s first), " Happy, " Cantrell St., South Philadelphia, Pa. (1937), through the exterior scene at the Ritz Bar, New York, N.Y. (1947-’48), the lost-soul portrait of Eddie, New York, N.Y. (1948), the almost menacing bus-stoppish group shot New York, N.Y. [Four women and poster of Barbara Stanwyck] (1949), and numerous other examples, his subjects are caught in the act of staring at something out of the frame.

(Note: Faurer seldom titled his photographs beyond their location, and he often noted divergent dates on the backs of identical prints; the dates that accompany the show’s titles, which themselves are sometimes supplemented with curators’ descriptive titles, cover the range of dates ascribed.)

Of course, it’s only practical to take candid photos when the subject is distracted, but in Faurer’s shots, the unseen object of his subject’s gaze is treated as an oblique compositional element — part of the vignette’s dynamic, even though we can’t see it. In other photographs, what occupies the subject’s attention is in plain sight — early works from Faurer’s home city like Manyunk Section of Philadelphia, Pa. (1937-’38), in which a small boy watches a man fumble out of a market with a double armful of melons, and Philadelphia, Pa. [Boy with shopping bags] (1938), a perspective shot in which a boy, inexplicably dangling a dozen empty shopping bags, leans on a pole as he studies an old woman conducting some undefined business — yet there’s no question that Faurer and the viewer are watching the watcher.

When Faurer’s compositions don’t involve external sightlines, they often obsess on internal ones. In a montage-inspired style similar to the approach perfected in the 1970s by Lee Friedlander, Faurer would frame his subjects with out-of-focus foreground elements, shoot through reflections, and expand a scene’s perspective by incorporating windows and mirrors. He perfected the resulting layers of subject and shadow subjects into a powerful compositional tool that was capable of inverting foreground and background and even incorporating a cityscape at the photographer’s back into the frame. He was a darkroom wizard who manipulated minute tonal values to bring clarity out of clutter. His Self-Portrait, 42nd Street El Station Looking Towards " Tudor City " (1946) is a masterpiece of visual confusion. There’s no mistaking the subject, but the inside-out receding perspective created by what appears to be a reflection in a mirror shot through a window and outlined by a silhouette of the subject (Faurer) occluding the cityscape reflected in the window is baffling. Similar indescribable effects can be found in Staten Island Ferry/I Once Dreamed About the Most Beautiful City in the World (1946) and Market Street, Philadelphia, Pa. [Man’s face seen through mannequin’s legs] (1937-’45). Try deconstructing the abstract dynamics of Faurer’s " race for the train " print Win, Place, and Show, 3rd Ave. El at 53rd St., New York, N.Y. (1946-’48) into tangible elements. It’s confounding.

At times, you suspect Faurer of double-exposures or multi-image printing, and at times, you’d be right. According to the show’s catalogue (Merrell, 208 pages, $40), the photo titled George Barrows in Robert Frank’s Loft, New York, N.Y. (1947-’49) includes an image of an African mask superimposed, in the darkroom, over Barrows’s face. And the surreal Accident, New York, N.Y. (1949-’52), which shows a shivering boy turning away from the chalk outline of an accident victim on the pavement and toward what looks like a wedding scene, is indeed an accidental double exposure. But for the most part, the illusionary visions are real. And they’re not just clever tricks. Faurer used his knack for seeing through the city environment’s confusion by embracing its funhouse-mirror chaos as a tactic that imparted motion and meaning to pedestrian scenes.

Faurer himself is something of an intangible figure. Born in Philadelphia and transplanted to New York in the mid 1940s, he spent decades of his career shooting fashion for Harper’s Bazaar, Mademoiselle, Glamour, and the like. (A few fashion shots are included in this show; ultimately, Faurer hated commercial work, but his minimalist 1948 Beauty in the Wind, shot for Junior Bazaar, deftly combines his street-art sensibility with the frivolousness of fashion-mag æsthetics.) He was mentored by legendary graphic designer Alexey Brodovitch and was close friends with documentary photographer Robert Frank. His street photography — honed in Philadelphia and perfected in Times Square — was known to critics and his photo-world contemporaries but got minimal public exposure through most of his lifetime.

From 1968, he spent six years working out of the country, then returned in ’74 and resumed shooting the streets of New York. But political and cultural sensibilities had shifted away from the familiar postwar mix of anxiety and prosperity, and his ’70s shots have a flat anachronistic edge — as if Vietnam-era Americans had somehow been time-traveled back into 1955 New York settings. He began to exhibit and lecture, but his shooting career was cut short in 1984 as the result of a debilitating traffic accident. He died in 2001, among the most accomplished and least heralded street photographers of his era.

That Faurer wasn’t famous in his day has more to do with his commercial preoccupations than with his relative skills. Amid the layered photographs and other genre elaborations in this retrospective is a majority of strong traditional street shots that, thanks in part to his exquisite printing skills, invariably evoke more than you expect. In Repaving Times Square, New York City (1950), the Manhattan crossroads is transformed into a carnival midway. The ultra-high-contrast Construction Site on Madison Ave. Looking Toward Rockefeller Center, New York, N.Y. (1947-’49) turns an incidental street scene into an exemplar of alienation. Union Square from Ohrbach’s Window, New York, N.Y. (1948-’50) renders a dusky intersection as a sentimental out-of-its-time landscape. Even the traditional street-photography subjects — mendicants, furtive couples, rich bastards, toughs — are recast by his camera from stereotypes into something more believable.

Critics have assigned intent to Faurer’s work beyond the degree of purposefulness usually afforded candid photographers. A placard at the Addison exhibit tells us he often positioned beggars at the side of the composition to emphasize " how society marginalizes these individuals " when more likely it was because beggars often sit on the margins of thoroughfares. But such forced analysis, antithetical to the realities of street shooting as it may be, is an understandable reaction to the way Faurer’s photographs, like those of Walker Evans (whom he idolized) transcend simple documentation. Statements are definitely being made, but they’re never pat and usually too complex for words.