He took his first painting lessons from Klaus Frieslander in 1940. In that same year, he also met Dimitris Pikionis and Nikos Hadjikyriakos-Ghikas, whom the artist himself considers his true teachers. From 1943 to 1949 he studied at the School of Fine Arts under Dimitrios Biskinis, Pavlos Mathiopoulos and Konstantinos Parthenis. Thanks to a scholarship he received from the Greek State Scholarships Foundation, he completed his studies at the Paris School of Fine Arts (1953-1956), where he was taught the art of chalcography by Édouard Goerg.
Starting his exhibition activity with his first solo show in 1948, he presented his work in solo and group painting and engraving exhibitions on a national and international level. Among others, he participated in the 1957 and 1965 Biennale of Sao Paolo and the 1959 Biennale of Alexandria, as well as in the International Engraving Exhibitions of Lugano in 1960 and Tokyo in 1964. In 1970, he was appointed the representative of Greece to the Venice Biennale but he refused to participate because of the junta in Greece at the time. He also took part in the exhibitions of the group “Armos A” (Junction A), which he had joined since 1949, as well as the group “Armos B”. In 1983, the series “Laiki Agora” (Farmers Market) was presented at the Greek National Gallery, where a retrospective exhibition of his work was held in 1999.
From 1951 onwards, he was a lecturer at the Faculty of Free Drawing of the National Technical University of Athens School of Architecture, and from 1958 to 1962 he taught at the Athens Technological Institute. In 1958, he was one of the founders of the Free College of Fine Arts (later to become the Vakalo Vocational School of Decorative Arts), where he taught until 1976, at which point he was elected professor at the Athens School of Fine Arts. He remained in that post until 1991, while in 1989 he was elected dean of the school. In 1993 he became a member of the Academy of Athens.
Staying true to representational painting and shaping a personal expressionist style of his own, Tetsis paints scenes of everyday life, portraits, landscapes and still lifes, paying particular attention to the role of color and light. His artistic creation also includes some involvement with engraving and mural painting of public buildings and churches.

• 

  Sifnos Ι