The need for encouragement of fresh talent and its fairly common concomitant, the audacity of youth, was never made more pointed then in "Fear and Desire," the drama fashioned by a tiny group of young, independent film makers, which arrived at the Guild Theatre yesterday. For, in essaying a dissection of the minds of men under the stress of war, Stanley Kubrick, a 24-year-old producer-director-photographer, and his equally young and unheralded scenarist and cast, have succeeded in turning out a moody, often visually powerful study of subdued excitements.

If "Fear and Desire" is uneven and sometimes reveals an experimental rather than a polished exterior, its over-all effect is entirely worthy of the sincere effort put into it. Photographed and produced on a comparative pittance (by Hollywood standards) on location in California's San Gabriel Mountains, the story is simplicity itself and unspecific as to time, place or people.

It is, as a narrator intones at the outset, "any war - the enemies do not exist unless we call them into being." And, since its theme is "the unchanging shapes of fear," Mr. Kubrick is concerned mainly with the conscious acts and the accompanying thoughts of four soldiers stranded behind the enemy's lines after their plane has been shot down, as well as the reactions of a girl whom they capture.

The lieutenant commanding them is an introspective flier, who has no overweaning desire to lead, but who realistically does so when the occasion demands it. His second in command, a sergeant, is a tough, common sort, outwardly untouched by the dread and desires of the rest of the company, whose only fear is that he will not achieve his moment in the sun - the capture or death of the enemy general, whom they spot in an outpost.

Then there is a callow, supersensitive youngster driven to literal distraction by fears, and a gentle, fourth soldier, who seems more tired than unnerved. The native girl, whose hatreds and horrors are unspoken but made pictorially apparent, is merely a terrified animal who comes to an untimely end after being trapped in a situation she never made.

If the depiction of their mental trials and tribulations is less successful than their attempt to reach the safety of their own lines, it may be laid to a script that occasionally is turgid and overly poetic, and to Mr. Kubrick's direction, which now and then is far from inspired. However, Mr. Kubrick's professionalism as a photographer should be obvious to an amateur. He has artistically caught glimpses of the grotesque attitudes of death, the wolfishness of hungry men as well as their bestiality, and in one scene, the wracking effect of lust on a pitifully juvenile soldier and the pinioned girl he is guarding.

Kenneth Harp plays the lieutenant (and the general) with restraint and understanding. He is torn by anxieties, but his distaste for war does not keep him from making decisions involving his life and those of his men. As the sergeant, Frank Silvera, the only member of the cast who has had experience in major films, is properly hard, muscular and disdainful of the less rugged members of the beleaguered band.

Paul Mazursky, as the frenetic youth, is only convincing in his more lucid movements. As the tired soldier, Steve Coit is given scant opportunity for striking histrionics, while Virginia Leith, the pretty brunette captive, whose dialogue is limited to one word, does project graphic timidity, loathing and terror, thanks to studied direction.

Although its script is more intellectual than explosive and its cast more garrulous than mobile, "Fear and Desire" evolves as a thoughtful, often expressive and engrossing view of men who have "traveled far from their private boundaries." And it augurs well for the comparative tyros who made it.