THERE’S NO BETTER place to begin talking about Arne Naess, Norwegian philosopher, ecologist, peace activist, and mountaineer, than on a mountainside. A particular mountain, in fact, called Hallingskarvet, somewhere off the Oslo-Bergen train line, in the wild and desolate high plateaus of Norway. On the slopes of this mountain, Naess has built himself a cabin, Tvergastein, a place he’s often returned to and used as a poetic and philosophic touchstone for his immense body of work.

Naess is more than an ordinary — if quite beloved — Norwegian. His theories and commitment to social justice remain an inspiration and a challenge. The Ecology of Wisdom only hints at the breadth and power of his thought. Born in Norway in 1912, Naess studied at the University of Oslo and received his doctorate there in 1936. In 1940, he joined the resistance to the German occupation of Norway, an experience which caused him to think hard about the obligation of defending one’s country but — for him — by nonmilitary means. Naess became a voice for Gandhian nonviolence and was strongly opposed to nuclear weaponry.

Climbing mountains, in Norway and elsewhere, was a minor obsession that was also the inspiration for Naess to reconsider the traditional understanding of the human relationship to nature, that is, the “shallow” environmentalism of stewardship that presupposes a hierarchy of beings. In 1973 he coined the phrase “deep ecology” as a means of valuing ecosystems and nonhuman species. “Deep ecology” was no sound bite; as a preeminent philosopher, Naess wanted to give his theories of ecosophy and biotic community a sturdy analytic foundation.

This collection of Naess’s writings, lucid, poetic, both accessible for the general reader and targeted for a more philosophically inclined audience, is culled from hundreds of articles and books. The editors have done a heroic job of placing the writings in the context of Naess’s life and larger concerns. They have arranged the book in thematic sections, beginning with Naess’s conception of the importance of singular places, including an ode to his mountain home of Tvergastein. There are articles about deep ecology and political issues as well as sections that reflect Naess’s methodology and his lifelong fascination with Spinoza.

If you’ve ever been to Norway, you know that there are hundreds of men and women like Arne Naess, nimble as goats into their nineties, attached beyond words to a harsh landscape of rock and glacier. The whole country has made a 180-degree turn in the last thousand years from pillaging, piracy, and general berserkery, to become a nation of peaceniks. It’s no mistake that while most of the Nobel Prizes are given out in Stockholm, the top honor for peace is bestowed in Oslo. “We seriously underestimate ourselves,” writes Naess. At a time when the environment hangs in the balance and it’s tempting to give in to despair, these sturdy, hopeful writings from an ecological philosopher and peace activist are more necessary than ever.