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black swan also Black Swan

noun [countable]

an event which is extremely rare and unexpected but has very significant consequences



'September 11, 2001 is a classic example of a Black Swan. It was only a failure of imagination by most Americans (including myself) to never have contemplated beforehand the possibility of such a dreadful day.'

Christian Science Monitor 22nd November 2012

'His story is now one that many people want to hear; how he and his crew averted disaster when one of the A380 Airbus engines blew up in flight, something he describes as a Black Swan Event.'

ABC, Australia 30th November 2012

Question: what do the rise of the Internet and the 2008 global financial crisis have in common? Answer: they are both considered to be black swans. Before anyone starts scratching their head and wondering why on earth either of these two things has anything to do with ornithology, then it might help if I explain that black swan is an expression now used to refer to any kind of unexpected but highly significant event.

one of the chief contexts in which the term black swan currently occurs is financial, especially in reference to the global economic turmoil of recent years

The phrase black swan is a metaphor describing an event which is unanticipated (perhaps because it seemed impossible or because no-one had considered it before), but which has very far-reaching consequences. The term occurs as a countable noun and is also often used as a modifying adjective which usually appears in the expression black-swan event.

Black-swan events are characterized by three main criteria: first, they are surprising, falling outside the realm of usual expectation; second, they have a major effect (sometimes even of historical significance); and third, with the benefit of hindsight they are often rationalized as something that could have been foreseen had the facts been examined carefully enough.

The terrorist attacks on the World Trade Center and the Pentagon on September 11th 2001 are often pinpointed as a classic example of a black swan. The attacks seemed unthinkable at that time, had far-reaching consequences which continue to be witnessed today (e.g. 'preventative' military offensives from Western governments) and in hindsight could have perhaps been predicted in the context of changes in terrorist tactics.

One of the chief contexts in which the term black swan currently occurs is financial, especially in reference to the global economic turmoil of recent years. Financial analysts have also extended the metaphor to talk about grey swans, events which are possible or known-about, and are potentially extremely significant, but which are considered by some to be unlikely. Among a group of recently identified grey swans in the financial domain is the so-called fiscal cliff, a cocktail of tax increases and spending cuts which could be disastrous for the US economy.

Background – black swan

Contemporary use of the expression black swan in reference to an unexpected but influential event is attributed to former market trader Nassim Nicholas Taleb, who first introduced it in his 2001 book Fooled by Randomness – The Hidden Role of Chance in Life and in the Markets. Taleb argued that the stock market was unpredictable and could be influenced by rare events or black swans, a controversial view which turned out to have some substance in the light of the economic crisis that followed. The expression later gained further popularity after Taleb went on to use it in the title of his 2008 book The Black Swan: The Impact of the Highly Improbable.

So, why black swan? The analogy is drawn from the discovery of black swans in Western Australia by Dutch explorer Willem de Vlamingh in the 17th century. At the time, Europeans had believed that all swans were white, so finding a black variety was a completely unexpected event which had never been experienced before. By extension then, a black swan is used to describe any phenomenon which occurs even though people think it impossible.

The current use of black swan seems likely to have been inspired by an archaic use dating back several hundred years, which was simply to refer to 'a person or thing which is extremely rare'.

by Kerry Maxwell, author of Brave New Words

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This article was first published on 12th March 2013.

Open Dictionary

fake news

a sensational piece of news which does not map to reality, created to attract attention or damage somebody's reputation

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