Arne Dekke Eide Næss ( AR-nə NESS; Urban East Norwegian: [ˈɑ̂ːɳə ˈdɛ̂kːə ˈæ̂ɪdə ˈnɛsː]; 27 January 1912 – 12 January 2009) was a Norwegian philosopher who coined the term "deep ecology", an important intellectual and inspirational figure within the environmental movement of the late twentieth century, and a prolific writer on many other philosophical issues. Næss cited Rachel Carson's 1962 book Silent Spring as being a key influence in his vision of deep ecology. Næss combined his ecological vision with Gandhian nonviolence and on several occasions participated in direct action.
Næss averred that while western environmental groups of the early post–World War II period had raised public awareness of the environmental issues of the time, they had largely failed to have insight into and address what he argued were the underlying cultural and philosophical background to these problems. Næss believed that the environmental crisis of the twentieth century had arisen due to certain unspoken philosophical presuppositions and attitudes within modern western developed societies which remained unacknowledged.
He thereby distinguished between what he called deep and shallow ecological thinking. In contrast to the prevailing utilitarian pragmatism of western businesses and governments, he advocated that a true understanding of nature would give rise to a point of view that appreciates the value of biological diversity, understanding that each living thing is dependent on the existence of other creatures in the complex web of interrelationships that is the natural world.
Næss was born in Slemdal, Oslo, Norway, the son of Christine (Dekke) and Ragnar Eide Næss. Ragnar was a successful banker, and Arne was the younger brother of shipowner Erling Dekke Næss. Næss had two children with his first wife Else and was the uncle of mountaineer and businessman Arne Næss Jr. (1937–2004).
In 1939, Næss was the youngest person to be appointed full professor at the University of Oslo and the only professor of philosophy in the country at the time.
He was a noted mountaineer, who in 1950 led the expedition that made the first ascent of Tirich Mir (7,708 metres or 25,289 feet) in Pakistan, depicted in the documentary film Tirich Mir til topps. The Tvergastein hut in the Hallingskarvet massif played an important role in the name of Næss's philosophy, "Ecosophy T", as "T" is said to represent his mountain hut Tvergastein.
In 1958, he founded the interdisciplinary journal of philosophy Inquiry.
In 1970, together with a large number of protesters, he chained himself to rocks in front of Mardalsfossen, a waterfall in a Norwegian fjord, and refused to descend until plans to build a dam were dropped. Though the demonstrators were carried away by police and the dam was eventually built, the demonstration launched a more activist phase of Norwegian environmentalism.
When he was 61, while guest-lecturing at the University of Hong Kong, he met Kit-Fai Tsui, a philosophy student who was four decades younger than him, whom he married seventeen years later.
In 1996, he won the Swedish Academy Nordic Prize, known as the "little Nobel". In 2005 he was decorated as a Commander with Star of the Royal Norwegian Order of St. Olav for socially useful work. Næss was a minor political candidate for the Norwegian Green Party in 2005.
Næss died on 12 January 2009, at the age of 96.
Næss's book Erkenntnis und wissenschaftliches Verhalten (1936) anticipated many themes familiar in post-war analytic philosophy.
In the 21st century, Næss came to be recognized by newer generations of philosophers as a pioneer of experimental philosophy (a term that Næss himself used) for his empirical semantics research. One of Næss's early publications on experimental philosophy was "Truth" as Conceived by Those Who Are Not Professional Philosophers (1938).
Næss's main philosophical work from the 1950s was entitled Interpretation and Preciseness (1953). This was an application of set theory to the problems of language interpretation, extending the work of semanticists such as Charles Kay Ogden in The Meaning of Meaning. A simple way of explaining it is that any given utterance (word, phrase, or sentence) can be considered as having different potential interpretations, depending on prevailing language norms, the characteristics of particular persons or groups of users, and the language situation in which the utterance occurred. These differing interpretations are to be formulated in more precise language represented as subsets of the original utterance. Each subset can, in its turn, have further subsets (theoretically ad infinitum). The advantages of this conceptualisation of interpretation are various. It enables systematic demonstration of possible interpretation, making possible evaluation of which are the more and less "reasonable interpretations". It is a logical instrument for demonstrating language vagueness, undue generalisation, conflation, pseudo-agreement and effective communication.
Næss developed a simplified, practical textbook embodying these advantages, entitled Communication and Argument: Elements of Applied Semantics (1966), which became a valued introduction to this pragmatics or "language logic", and was used over many decades as a sine qua non for the preparatory examination at the University of Oslo, later known as examen philosophicum ("exphil").
Recommendations for public debate
Næss's book Communication and Argument (1966) included his recommendations for objective public debate. Næss argued for adhering to the following principles to make discussions as fruitful and pleasant as possible:
"Avoid tendentious references to side issues"—distractions such as personal attacks, claims about opponents' motivation, or irrelevant explanations or arguments.