Peter Wessel Zapffe [pronounced ZAP-fe]was a Norwegian philosopher, author and mountaineer. He was well known for his somewhat pessimistic view of human existence and his philosophy is widely considered to be pessimistic, much like the earlier work of Arthur Schopenhauer, by whom he was inspired. His thoughts regarding the error of human existence are presented in the essay, The Last Messiah (original: Den sidste Messias, 1933). This essay is a shorter version of his best-known work, the philosophical treatise, On the tragic (original: Om det tragiske 1941). He called his brand of thought, biosophy, which he defined as "thinking on life".