Arne Dekke Eide Næss ( / ˈ ɑːr n ə ˈ n ɛ s / AR -nə NESS ; Urban East Norwegian: [ˈɑ̂ːɳə ˈdɛ̂kːə ˈæ̂ɪdə ˈnɛsː] ; January 27, 1912 – January 12, 2009) was a Norwegian philosopher who created the term "deep ecology." He was an important thinker and inspiration in the environmental movement of the late twentieth century. He also wrote many books about other philosophical topics. Næss said that Rachel Carson's 1962 book Silent Spring greatly influenced his ideas about deep ecology. He combined his views about the environment with the idea of nonviolence from Gandhi and took part in direct action several times.

Næss believed that environmental groups in the early years after World War II helped people understand environmental problems but did not fully recognize or address the deeper cultural and philosophical reasons behind these issues. He argued that the environmental problems of the twentieth century happened because of certain unspoken beliefs and attitudes in modern Western societies that were not widely acknowledged.

He talked about two types of thinking about the environment: deep and shallow. He disagreed with the practical approaches of Western businesses and governments that focused on benefits. Instead, he believed that truly understanding nature would lead to seeing the value of biological diversity. He explained that every living thing depends on other creatures in the complex network of relationships that make up the natural world.

Life and career

Arne Næss was born in Slemdal, Oslo, Norway, to Christine (Dekke) and Ragnar Eide Næss. Ragnar was a successful banker, and Arne was the younger brother of Erling Dekke Næss, a shipowner. Arne had two children with his first wife, Else, and was the uncle of Arne Næss Jr., a mountaineer and businessman who lived from 1937 to 2004.

In 1939, Næss became the youngest person ever appointed as a full professor at the University of Oslo. At that time, he was the only professor of philosophy in Norway.

Næss was also a famous mountaineer. In 1950, he led an expedition that reached the top of Tirich Mir, a mountain in Pakistan that is 7,708 meters (25,289 feet) high. This event was shown in a documentary film called Tirich Mir til topps. A mountain hut named Tvergastein in the Hallingskarvet massif was important to Næss’s philosophy called "Ecosophy T." The letter "T" in this name is believed to stand for the hut Tvergastein.

In 1958, Næss started a journal called Inquiry, which focuses on philosophy and combines ideas from many different fields.

In 1970, Næss joined many other protesters who tied themselves to rocks near Mardalsfossen, a waterfall in a Norwegian fjord. They refused to leave until plans to build a dam were canceled. Although the dam was eventually built and the protesters were removed by police, the protest helped start a more active movement for environmental protection in Norway.

At age 61, while teaching at the University of Hong Kong, Næss met Kit-Fai Tsui, a philosophy student who was 40 years younger. They married 17 years later.

In 1996, Næss received the Swedish Academy Nordic Prize, often called the "little Nobel." In 2005, he was honored as a Commander with Star of the Royal Norwegian Order of St. Olav for his work that helped society. Næss also ran as a minor candidate for the Norwegian Green Party in 2005.

Næss died on January 12, 2009, at the age of 96.

Philosophy

Næss's book Erkenntnis und wissenschaftliches Verhalten (1936) introduced ideas that became important in philosophy after World War II.

In the 21st century, newer generations of philosophers recognized Næss as a pioneer of experimental philosophy (a term he used). One of his early works on this topic was “Truth” as Conceived by Those Who Are Not Professional Philosophers (1938).

Næss’s main philosophical work from the 1950s was Interpretation and Preciseness (1953). This book used set theory to explore how language can be interpreted. It built on the work of scholars like Charles Kay Ogden in The Meaning of Meaning. A simple explanation is that any word, phrase, or sentence can have multiple meanings, depending on language rules, the people or groups using it, and the situation in which it is used. These different meanings can be described more clearly as smaller groups (subsets) of the original idea. Each subset can also be broken into smaller groups, and this process can continue endlessly. This method helps show how language can be unclear, overly broad, or misleading, and it supports clearer communication.

Næss created a practical textbook called Communication and Argument: Elements of Applied Semantics (1966). This book explained the ideas from his earlier work and became an important tool for learning about language logic. It was required reading for a philosophy exam at the University of Oslo, later called examen philosophicum.

In Communication and Argument (1966), Næss shared guidelines for fair and effective public debate. He suggested following these principles to make discussions more productive and respectful:

• Avoid talking about unrelated topics, such as personal attacks or irrelevant arguments.
• Do not misrepresent others’ views by changing quotes or paraphrasing in a misleading way.
• Avoid using unclear or vague statements instead of precise ones.
• Do not claim that others believe something they do not.
• Do not share incomplete or false information, such as hiding important details.
• Avoid using emotional or persuasive techniques, like sarcasm, exaggeration, or threats, to influence others.

These guidelines were part of a required philosophy course in Norwegian universities for many years.

Erik Krabbe, an argumentation theorist, later said that Næss’s debate rules were early examples of the principles used in the study of critical discussion.

Ecosophy T, different from deep ecology, was the name of Næss’s personal philosophy. Some scholars, like Warwick Fox, linked deep ecology to Næss’s beliefs. The “T” in ecosophy T refers to Tvergastein, a mountain hut where Næss wrote many of his books. He believed everyone should develop their own personal philosophy.

Næss’s ecosophy focused on self-realization. He believed all living beings—humans, animals, and plants—have an equal right to live and thrive. He argued that humans can become part of Earth’s ecosystems through self-realization, rather than focusing only on themselves. One writer summarized Næss’s ethical view as: If you are unsure how your actions will affect others, you should not act.

In a summary of Næss’s career, Nina Witoszek noted that he often used the phrase “in principle” to qualify his strongest ideas. He also acknowledged that in practice, people must sometimes make compromises, and real-life actions may not always match strict ideals.

Selected works

• Næss, Arne (1936). Erkenntnis und wissenschaftliches Verhalten. Works published by the Norwegian Academy of Science and Letters in Oslo. 2. Hist.-filos. class, 1936 (in German). Vol. 1. Oslo: I kommisjom hos J. Dybwad. OCLC 5916296.
• Næss, Arne (1938). “Truth” as Conceived by Those Who Are Not Professional Philosophers. Works published by the Norwegian Academy of Science and Letters in Oslo, II. Hist.-filos. class, 1938, no. 4. Oslo: I kommisjon hos J. Dybwad. OCLC 1021167.
• Næss, Arne (1953). Interpretation and Preciseness: A Contribution to the Theory of Communication. Works published by the Norwegian Academy of Science and Letters in Oslo. 2. Hist.-filos. class, 1953, no. 1. Oslo: I kommisjon hos J. Dybwad. OCLC 3195596.
• Næss, Arne; Christophersen, Jens A.; Kvalø, Kjell (1956). Democracy, Ideology, and Objectivity: Studies in the Semantics and Cognitive Analysis of Ideological Controversy. Oslo: Published for the Norwegian Research Council for Science and the Humanities by University Press. OCLC 1942421.
• Næss, Arne (June 1958). “A systematization of Gandhian ethics of conflict resolution”. Journal of Conflict Resolution. 2 (2): 140–155. doi: 10.1177/002200275800200202. JSTOR 172972. S2CID 144823357.
• Næss, Arne (1965). Gandhi and the Nuclear Age. Totowa, NJ: Bedminster Press. OCLC 368861.
• Næss, Arne (1966). Communication and Argument: Elements of Applied Semantics. Translated by Alastair Hannay. Totowa, NJ: Bedminster Press. OCLC 1012411.
• Næss, Arne (1968) [1965]. Four Modern Philosophers: Carnap, Wittgenstein, Heidegger, Sartre. Translated by Alastair Hannay. Chicago: University of Chicago Press. OCLC 252616. Translation of Moderne filosofer.
• Næss, Arne (1968). Scepticism. International Library of Philosophy and Scientific Method. New York: Humanities Press. ISBN 9780710036391. OCLC 1283.
• Næss, Arne (1973). “The shallow and the deep, long-range ecology movement: a summary” (PDF). Inquiry: An Interdisciplinary Journal of Philosophy. 16 (1–4): 95–100. doi: 10.1080/00201747308601682. S2CID 52207763.
• Næss, Arne (1975) [1972]. Freedom, Emotion and Self-Subsistence: The Structure of a Central Part of Spinoza's Ethics. Filosofiske problemer. Vol. 42. Oslo: Universitetsforl. ISBN 8200014592. OCLC 3841538.
• Næss, Arne (Fall 1984). “A defence of the deep ecology movement”. Environmental Ethics. 6 (3): 265–270. Bibcode: 1984EnEth…6..265N. doi: 10.5840/enviroethics19846330.
• Næss, Arne (Winter 1986). “The deep ecological movement: some philosophical aspects”. Philosophical Inquiry. 8 (1/2): 10–31. doi: 10.5840/philinquiry198681/22.
• Naess, Arne (1987). “Self-realization: an ecological approach to being in the world”. The Trumpeter. 4 (3): 35–42.
• Næss, Arne (1989) [1976]. Ecology, Community and Lifestyle: Outline of an Ecosophy. Translated by David Rothenberg. Cambridge, UK; New York: Cambridge University Press. doi: 10.1017/CBO9780511525599. ISBN 0521344069. OCLC 17621528. “Not a direct translation of Arne Næss' 1976 work, Økologi, samfunn, og livsstil, but rather a new work in English, based on the Norwegian, with many sections revised and rewritten by Professor Næss.”
• Rothenberg, David; Næss, Arne (1993). Is It Painful to Think?: Conversations with Arne Næss. Minneapolis: University of Minnesota Press. ISBN 0816621519. JSTOR 10.5749/j.ctttspr2. OCL