THOSE WHO DO CLIMB mountains take scant interest in the motives of those who don't, but the reverse does not hold. Non-climbers seem to be endlessly fascinated with the why of climbing. Surely George Mallory's tautological explanation for his desire to scale Mt. Everest -- "because it is there" -- was in part an effort to stifle the question once and for all. The effort failed: the question is still rampant, and these books suggest diverging answers to it.

Michael Tobias and Harold Drasdo's anthology, The Mountain Spirit , proposes that man is drawn to mountains because they are spiritually charged. For Western religions mountains are closer to heaven than the rest of the earth: they enjoy a kind of sacredness by proximity. For Eastern religions mountains have a useless self-signifying quality which makes them paradigms of that wholeness and self-contentedness which man should nurture in himself.

Sad to say, many of the selections in The Mountain Spirit are farragoes of abstract sentiment and academic prose. (Tobias has a Ph.D. from the History of Consciousness department at the University of California at Santa Cruz.) One 13th-century Japanese sage is represented by this enigma manque. "An ancient Buddha has said, 'Mountains are mountains and rivers are rivers.' The meaning of these words is not that mountains are mountains, but that mountains are mountains." Well, that is certainly something to chew over.

In refreshing contrast, Chris Jones' book avoids the ineffable like an armchair. Climbing in North America is a storehouse of mountaineering thrills, innovations in technique, personalities and ribaldries. Jones is especially good on the psychology of climbers, which is not always as nobly rarefied as the high-altitude air they breathe. Some climbers are possessive about mountains they've been planning to conquer: a proprietary Alaskan once reacted to the rumor that Fred Beckey was going after the peaks of the Juneau Icefield by writing a letter of warning. Jones notes, "It was the incentive Beckey needed." Others assert the same authority over climbs they've already made. "Broken Sling was such a noted super climb that when it became clear others might begin to repeat the route, Dave Craft reputedly chopped off a key hold to keep away the riffraff."

Jones also reminds us that mountain-climbing lends itself to fabrication. The climbing party is usually small enough to contain a deception, and failure to reach the summit can be unbearably disheartening. A few parties have succumbed to the temptation to boast of a pinacle which in fact they did not attain.

Jones implies, however, the false claims rarely endure. Usually there is something funny about them, such as the climbers' vagueness as to the look of the summit. The combination of a suspicious account and the abiding passion to be first all but insures that another party will make the real climb and discover the fraud. One group destroyed Frederick Cook's claim to the first ascent of Mt. McKinley -- a 20,320 from the highest point on the continent -- by locating the exact spot, on a lesser summit,where he took a phony photograph. George Kinney's claim on Mt. Robson, the highest peak in the Canadian Rockies, is generaly discredited because his account fails to mention the prominent ice gargoyles on the summit ridge.

Galen Rowell may be the foremost American practitioner of that hybrid art, photojournalism. His superb photographs in High and Wild are appropriately angular and soaked with color. Viewed together, they give the impression that Rowell has somehow overcome time: otherwise there's no accounting for his presence at so many sites of beauty on the verge of evanescence.

He is also an energetic storyteller, as witness this excerpt from the last chapter, "A One-Day Ascent of Mount McKinley." Halfway up the mountain, Rowell and his friend Ned Gillette were obliged to change from skis to crampons. When they stopped to make the switch, "Ned's ski edges suddenly slid, and he plummeted toward a cliff, sixty feet away. Ned and I were roped together with our ice axes cleverly lashed to our packs, well out of reach. In the seconds before the rope pulled tight, I jammed the tip of a ski pole into the ice in a futile attempt at a self-arrest; then a tremendous jerk at my waist launched me toward Ned's falling form. . . .

"A mere arm's length from the cliff, I stopped -- face first against Ned's steel ski edges. Our individual actions, unknown to each other, had cooperated to save our lives. My self-arrest had failed, but not before it slowed Ned for a split second, enabling him to grab a fixed rope left by an earlier expedition as he fell head first on his back. Adrenalin gave his gloved hand a death grip on the quarter-inch polyproplene. Had he not stopped with his skis in the air, I would have fallen past him and pulled us both off the cliff."

While Rowell and Gillette inch themselves back up, we can legitimately shake our heads and rephrase the original question: Why would anyone engage in a sport in which survival so frequently hinges on sheer happenstance? Jones furnishes what I take to be the answer when he explains why it took so long for mountaineering to catch on in North America. "Everyday like in the new territories was a continual challenge. The pioneers might enjoy a good scramble up Pikes Peak, but they had no need to risk their necks to get a feeling of accomplishment. Life itself was accomplishment enough."

There's no call, then, for invoking a supernatural purpose for mountainclimbing: Jones's earthbound theory seems ample. Physical challenge long ago departed from the vast majority of Americans' everyday lives. And even for those equipped to meet them, intellectual challenges may not suffice. There seems to be a deep-rooted human need not to take living entirely for granted, and for a climber a measure of jeopardy enhances life.