Duck test

Looks like a duck , walks like a duck ...

... swims like a duck, croaks like a duck: That 's a duck.

The Terminus duck test ( English test duck ) describes a method of analog definition , the nature of a particular phenomenon only by its outside visible behaviors and characteristics to understand and analyze. The principle of the method is:
"If it looks like a duck, swims like a duck and croaks like a duck, then it is probably a duck."

Concept emergence

While no one consciously uses the duck test because it is considered an inherent sign of human intuition , the poet James Whitcomb Riley has dedicated a poem to the metaphors underlying the term :

"When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck."

"When I see a bird that walks like a duck and swims like a duck and croaks like a duck, I call that bird a duck."

However, the original origin of this phrase is disputed.

Use of terms

US foreign policy

The term probably became a political catchphrase in the USA in 1950 during the Cold War by Richard Patterson . Patterson was the US ambassador to Guatemala during the administration of Jacobo Árbenz Guzmán . He explains his assessment that the government is communist as follows:

“Suppose you see a bird walking around in a farm yard. This bird has no label that says 'duck'. But the bird certainly looks like a duck. Also, he goes to the pond and you notice that he swims like a duck. Then he opens his beak and quacks like a duck. Well, by this time you have probably reached the conclusion that the bird is a duck, whether he's wearing a label or not. "

“Suppose you see a bird waddling around on a farm. This bird does not have a sign that says 'duck'. But this bird clearly looks like a duck. When he goes to the pond, you also find that he swims like a duck. Then it opens its beak and croaks like a duck. Well, by this point you have probably come to the conclusion that the bird is a duck whether it is labeled or not. "

- Richard Patterson

To Patterson and several other US officials, it looked like Arbenz's government would be undermined by communist machinations. It didn't take long for US politicians to believe that Arbenz's regime was communist in nature, instead of checking whether a communist regime actually exists and is promoting agrarian reform , as such reform was also in Mao Zedong's revolution in China 1949 played a leading role. The CIA was authorized by President Dwight D. Eisenhower to overthrow the government of Guatemala with Operation PBSUCCESS .

Philosophy of science

The term duck test is only used to describe the process of attributing an unknown identity based on its visible appearances. These attributions are based on the subjective experiences of the respective person and are only suitable for scientific purposes to a limited extent.

programming

Duck typing is a concept of object-oriented programming in which the type of an object is not described by its class , but by the existence of certain methods or attributes .

supporting documents

^ Richard H. Immerman: The CIA in Guatemala: The Foreign Policy of Intervention . University of Texas Press, Austin (Texas) 1982, pp. 102 .

[Immerman-1] Richard H. Immerman: The CIA in Guatemala: The Foreign Policy of Intervention . University of Texas Press, Austin (Texas) 1982, pp. 102 .