Chicken or the egg

The chicken or the egg is a reference to the causality dilemma which arises from the expression "which came first, the chicken or the egg?" Since the chicken emerges from an egg, and the egg is laid by a chicken, it is ambiguous which originally gave rise to the other. Chickens always come from eggs upon which a chicken has sat. The usual point outside of logic, however, is one of infinite regression since an egg was caused by a chicken, which was caused by an egg, etc. The chicken and egg dilemma is often appealed to in pointing out the futility of identifying the original cause in any issue of cyclical cause-and-effect.

History of the problem

The earliest reference to the dilemma is found in Plutarch's Moralia, in the books titled "Table Talk," in a series of arguments based on questions posed in a symposium. Under the section entitled, "Whether the hen or the egg came first," the discussion is introduced in such a way suggesting that the origin of the dilemma was even older:

"...the problem about the egg and the hen, which of them came first, was dragged into our talk, a difficult problem which gives investigators much trouble. And Sulla my comrade said that with a small problem, as with a tool, we were rocking loose a great and heavy one, that of the creation of the world..."

Various answers have been formulated in response to the question, many of them humorous.

As suggested by the alternative definitions and solutions given below, the chicken-or-egg dilemma has multiple semantic variants and can thus be viewed as an exercise in semantics. Regarding at least two of these variants, the field of biology contains decisive contextual information. Although the problem has been around in one form or another for millennia, making it difficult or impossible to know who first solved it, the biological information needed to resolve all of the obvious semantic variants has only been available for decades while the axiomatic solution has been around since the time the question was first raised.

A modern analysis covering all of the major variants was authored by Christopher Langan, published in 2001 on the Mega Foundation website , and subsequently included in his book of essays, The Art of Knowing . It appeared again in The Improper Hamptonian , was included in abbreviated form in a 2001 Long Island Newsday Q&A column featuring Langan , and was compactly summarized in Langan's 2001 Popular Science interview.

A CNN article on May 26, 2006 featured an analysis, according to which the egg came first The key criteria on which CNN bases its answer, involving relatively recent findings from reproductive and evolutionary biology, are identical to several of those cited in the prior analysis.

Assuming a chicken egg

In this case, the egg is assumed to be a chicken's egg. This is an obvious assumption since the question itself implies a link between the two.

If one assumes the egg to be a chicken egg then one must define what a chicken egg is:

• If: A chicken egg will hatch a chicken

Then a bypass is allowed: An animal that was not a chicken laid the chicken egg which contained the first chicken. In this case the egg came first.

• If: A chicken egg is the egg that a chicken lays

Then a bypass is allowed: A chicken (that hatched from a non-chicken egg) laid an egg (a chicken egg). In this case the chicken came first.

• If: A chicken egg will hatch a chicken and was laid by a chicken

Then there may be an error of definition. If the definition of "chicken" used does not refer to "chicken eggs," then the chicken must come first, because without chickens there cannot be any chicken eggs.

Theological answers

According to creationists who believe in Biblical inerrancy, birds were created "on the fifth day" as adolescents or adults. Since there is no reference to the creation of eggs, they presumably were then made by chickens afterwards by the normal process. Therefore, the chicken came first.

Alternatively, for those who accept the intelligent design form of creationism, Eugene Volokh has noted that "In my experience, most creationists are also pro-life -- in which case, the egg is a chicken." [1]

A question of syntax

One can consider the question inside the framework of experience, making the question concrete instead of abstract: "The chicken or the egg - which came first?" "The chicken" came first - in the sentence of the question. If the question is phrased differently, the answer is different.

Cyclical cause-and-effect

There are many real world examples of cyclical cause-and-effect, in which the chicken-or-egg question helps identify the analytical problem:

• Fear of economic downturn cause people to spend less, which reduces demand, causing economic downturn
• Fear of violence/war can make people more defensive/violent, the resulting tension/violence will cause more fear.
• More jobs cause more consumption, which requires more production, and thus more jobs.

See also

• Why did the chicken cross the road? (Problems with chickens beyond which came first)
• Catch-22 (logic)
• Bootstrapping (compilers), i.e., how to write a compiler for a previously uncompiled language using the language itself.
• Positive feedback
• Mother and Child Reunion

References

• CNN.com - Chicken and egg debate unscrambled
• ChickenEgg.org - Vote for which came first