From today's featured article
![Carl Sagan with a mock-up of a Viking lander](http://upload.wikimedia.org/wikipedia/commons/thumb/9/95/Sagan_large.jpg/171px-Sagan_large.jpg)
The Sagan standard is the aphorism that "extraordinary claims require extraordinary evidence". It is named for Carl Sagan (pictured), who used the phrase in his 1979 book Broca's Brain. The standard has been described as fundamental to the scientific method and is regarded as encapsulating the basic principles of scientific skepticism. The Sagan standard is similar to Occam's razor in that both prefer simpler explanations to more complex ones. The Sagan standard is often invoked to challenge data and scientific findings, or to criticize pseudoscientific claims. Similar statements were previously made by figures such as Thomas Jefferson in 1808, Pierre-Simon Laplace in 1814, and Théodore Flournoy in 1899. The formulation "Extraordinary claims require extraordinary proof" was used a year prior to Sagan, by scientific skeptic Marcello Truzzi. It has also been argued that philosopher David Hume first fully characterized the principles of the Sagan standard in his 1748 essay "Of Miracles". (Full article...)
Did you know ...
- ... that the 1866 barque Thoon Kramom (pictured) has a replica serving as a floating restaurant?
- ... that Will Smith took part in the expedition that discovered the northern green anaconda?
- ... that at the age of 28, Mason Morelli became the first player in Vegas Golden Knights franchise history to record two points in their National Hockey League debut game?
- ... that the Kīlauea lava cricket disappears from a lava field as soon as any plants start to grow there?
- ... that the British political theorist Chris Armstrong has called for a "blue new deal" to secure ecological resilience for the ocean and a just blue economy?
- ... that Songs from Suicide Bridge was recorded in a repurposed tool shed?
- ... that several organisers of the Hindu Mela were involved in a secret society that manufactured matchsticks?
- ... that Julian Assange's lawyer argued that the rules set by the Ecuadorian embassy requiring Assange to take care of his pet cat Michi were "denigrating"?
In the news
- At the Academy Awards, Oppenheimer (director Christopher Nolan pictured) wins seven awards, including Best Picture.
- Japanese manga artist Akira Toriyama, author of Dragon Ball, dies at the age of 68.
- Sweden becomes the thirty-second member state of NATO.
- The Haitian government declares a state of emergency after gangs storm two prisons and demand the resignation of Prime Minister Ariel Henry.
On this day
- 1537 – Croatian–Ottoman wars: After the execution of feudal lord Petar Kružić, Croatian forces at Klis surrendered to the Ottoman forces in exchange for their safe passage to northern locations.
- 1881 – Andrew Watson (pictured) captained the Scotland national football team against England, becoming the world's first black international footballer.
- 1947 – Cold War: U.S. president Harry S. Truman proclaimed the Truman Doctrine to help stem the spread of communism.
- 1952 – British diplomat Lord Ismay was appointed the first secretary general of NATO.
- 1971 – The Turkish Armed Forces executed a "coup by memorandum", forcing the resignation of Prime Minister Süleyman Demirel.
- 2006 – U.S. Army soldiers gang-raped a 14-year-old Iraqi girl and murdered her along with her family members.
- William Henry Perkin (b. 1838)
- Gemma Galgani (b. 1878)
- Zhao Wei (b. 1976)
- Arina Tanemura (b. 1978)
Today's featured picture
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The eastern chipmunk (Tamias striatus) is a chipmunk species found in eastern North America. It is a small species, reaching about 30 centimetres (12 in) in length, with a weight of 66 to 150 grams (2.3 to 5.3 oz). It has reddish-brown fur on its upper body and five dark brown stripes contrasting with light brown stripes along its back, ending in a dark tail. The eastern chipmunk can climb trees well, but constructs underground nests with extensive tunnel systems, often with several entrances. Its vocal repertoire consists of five sounds: the chip, the chuck, the trills, the whistle or squeal, and chatter. Trills have been measured to occur at the rate of 130 vibrations per minute. The eastern chipmunk lives a solitary life, except during courtship and mating and for the short period that young spend with their mothers after birth. It sometimes hibernates during the winter. This eastern chipmunk with stuffed cheeks was photographed in Prospect Park in Brooklyn, New York. Photograph credit: Rhododendrites
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