Marcello Truzzi

Truzzi's remark is derived from the 18th century French mathematician Pierre-Simon de Laplace's "plus un fait est extraordinaire, plus il a besoin d'être appuyé de fortes preuves" (the more extraordinary a fact is, the more it needs to be supported by strong evidence). Carl Sagan later popularized Truzzi's adaptation of Laplace as "Extraordinary claims require extraordinary evidence", which came to be known as the Sagan standard.

In 2017, World Scientific released a book edited by Dana Richards about the correspondence between Martin Gardner and Truzzi. The book called Dear Martin, Dear Marcello: Gardner and Truzzi on Skepticism is broken up into four sections; "The Road to CSICOP", "The Demarcation Problem", "The Dissolution", and the "Return to Cordiality". The early letters from Truzzi were not preserved and the beginning of the book seems one-sided with only Gardner's letters. The editor, Richards states in the introduction the conflicts between the two men, their differing goals for CSICOP, and various people in the skeptic and paranormal communities. They discuss many topics including publishers, Geller, and the "definitions of charlatan and crankpot".

In 1994 Susan Blackmore, a parapsychologist who became more skeptical and eventually became a CSICOP fellow in 1991, described what she termed the "worst kind of pseudoskepticism":

While a Professor of Sociology at Eastern Michigan University in 1987, Truzzi discussed pseudoskepticism in the journal Zetetic Scholar which he had founded:

Although he was familiar with folie à deux, Truzzi was confident a shared visual hallucination could not be skeptically examined by one of the participators. Thus he categorized it as an anomaly. In a 1982 interview Truzzi stated that controlled ESP (ganzfeld) experiments had "gotten the right results" maybe 60 percent of the time. This question remains controversial. Truzzi remained an advisor to IRVA, the International Remote Viewing Association, from its founding meeting until his death.

Truzzi was Keynote Speaker at the 1st annual National Roller Coaster Conference, "CoasterMania", held at Cedar Point Amusement Park, Sandusky, Ohio, in 1978. On the subject of riding in the front vs riding in the back of a roller coaster, he said:

Truzzi founded the skeptical journal Explorations. In 1976, Truzzi was a founding member of the skeptic organization CSICOP and served as its co-chairman along with Paul Kurtz. Truzzi's journal became the official journal of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP) and was renamed The Zetetic ("zetetic" is another name for "skeptic" and is not to be confused with zetetics, the study of the relationship of art and science). The journal was under his editorship for the first year, until August 1977. He left CSICOP about a year after its founding, after receiving a vote of no confidence from the group's Executive Council. Truzzi wanted to include pro-paranormal people in the organization and pro-paranormal research in the journal, but CSICOP felt that there were already enough organizations and journals dedicated to the paranormal. Kendrick Frazier became the editor of CSICOP's journal and the name was changed to Skeptical Inquirer.

A professor of sociology at Eastern Michigan University from 1974–2003, Truzzi served as the chair of the sociology department from 1974 to 1985.

Truzzi also taught at Cornell, the University of South Florida, the University of Michigan, and the New College of Florida. His 1968 textbook, “Sociology in Every Day Life,” was a best-seller.

Truzzi earned several degrees in sociology: his Bachelor of Arts from Florida State University in 1957, his Master of Arts from the University of Florida in 1962, and his doctorate from Cornell University in 1970. He served in the United States Army between 1958 and 1960; he became a naturalized citizen in 1961.

Truzzi was born in Copenhagen, Denmark, and was the only child of juggler Massimiliano Truzzi and his wife Sonya. His family moved to the United States in 1940 where his father performed with the Ringling Bros. and Barnum & Bailey Circus.

Marcello Truzzi (September 6, 1935 – February 2, 2003) was a professor of sociology at New College of Florida and later at Eastern Michigan University, founding co-chairman of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP), a founder of the Society for Scientific Exploration, and director for the Center for Scientific Anomalies Research.