Sigmund Kvaløy Setreng (20 September 1934 – 27 May 2014)[1] was a Norwegian philosopher, illustrator, mountain climber, environmental activist and politician.

[2][3] Setreng was born in Trondheim to schoolteachers Anders Kvaløy and Kirsti Sætereng, and grew up in Lom.

Interested in nature and environmental protection, and influenced by Arne Næss, Peter Wessel Zapffe and Henri Bergson, he eventually developed his own original variant of ecophilosophy.

An able mountain climber, he travelled to Rolwaling Himal to study the Sherpa people native to Nepal and the Himalayas, and fascinated by their way of thinking, he converted to Buddhism.

In the late 1970s he was engaged in the Alta controversy and in protests against construction of the Innerdalsvatnet dam in the Orkla River.