Arnold Gehlen (29 January 1904 – 30 January 1976) was an influential conservative German philosopher, sociologist, and anthropologist.
He was part of the "'Leipzig School" under Hans Freyer. Gehlen joined the NSDAP in 1933. However, even Wikipedia does not accuse him of supporting National Socialism ideologically and after "denazification" he was able to return to academia in the postwar period.
Influenced by recent research such as that by the ethologist Konrad Lorenz, Gehlen emphasized concepts such as the "world openness" of humans, referring to humans being much less specialized for a specific environment than other animals. Consequently, they also have weak specific instincts, but at the same time have strong more general instincts, such as non-seasonal sexuality. This may cause various problems for humans and their societies. Gehlen therefore emphasizes the importance of beneficial institutions and traditions for humans in order to give them and society positive meanings and purposes.