Chicken and egg problem

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The chicken-and-egg problem - expressed by the phrase “which came first: the hen or the egg ?” - is a phrase that describes an unanswerable question about the original trigger of a causal chain , the events of which represent mutually cause and effect. Mathematically, there is a chicken and egg problem when relationships cannot be sorted topologically, i.e. they do not form a partial order .

history

From the Tacuinum Sanitatis , 14th century

The question of whether the egg or the hen came first already played a role in philosophical discussions in antiquity . Plutarch dedicates a chapter to her in his table talks. In the Saturnalia of Macrobius the question is treated in a very similar way.

In popular representations, the question is occasionally associated with Aristotle , for example with François Fénelon or Helena Petrovna Blavatsky . There it says:

“If there was a first human being, then he must have been born without a father or mother - which is contrary to nature, because there could not have been a first egg to give birth to birds, or there should have been a first bird that Eggs started; because the bird comes from an egg. "

Areas of application

philosophy

logic

In logic , the chicken and egg problem is a metaphor and questions whether there is a final justification, that is, a “reason in itself”, as Arthur Schopenhauer puts it. As an example, Schopenhauer cites the falling of an object. Why does a stone fall down? Any answer, e.g. B. here “Because of the attraction ”, one can immediately further question: “Why is there an attraction?” Etc. What at first glance looks like the question of the reason is actually only the question of the cause .

The difference between cause and reason becomes clear when one realizes that a cause is only ever conceivable in a causal chain with a timeline . The reason is only one if it forms the foundation and is not itself a consequence of something.

The problem is presented in detail in About the fourfold root of the theorem of sufficient reason by Schopenhauer.

ethics

In ethics , the chicken-and-egg problem stands in the neighborhood of the tautology problem in the (lack of) justifiability of ethical action, which ends in a circular argument or is based on itself.

For example, Immanuel Kant does not look for the justification for moral action in causality, such as the sentence “like you for me, so I for you”, because he states that the foundation is unsatisfactory. In the case of "like you to me, so I to you" (biblical an eye for an eye, a tooth for a tooth ), one cannot speak of moral action, because I always base my behavior on the behavior of the other and they (possibly) do the same. If both do bad things and justify it with the fact that the other does it too, that is undoubtedly not moral action and must therefore be rejected as the basis of moral action. It leads to the chicken and egg problem. From this, Kant develops the categorical imperative : "Act only according to the maxim by which you can also want it to become a general law."

rhetoric

The chicken and egg metaphor can be a rhetorical tool in an argument.

biology

Still an egg or already a chick?
Frog spawn: eggs without a shell

When Charles Darwin propagated his theory of evolution as a justification for the development of the different forms of life on earth and this idea gradually began to gain acceptance in science and in the course of the 20th century also in theological doctrine, the question arose which came first , the hen or the egg, placed against the backdrop of the theory of evolution.

From today's scientific point of view, the specific question about the origin of the animal chicken is no longer a chicken -and-egg problem , as it has evolved, i.e. in the biological sense neither a “first chicken” nor a “first chicken egg” existed, but rather the succession of generations itself, through many small adjustments, has become today's "chicken and egg succession". This view is also applicable to metaphorical use.

Based on current scientific point of view, the ancestors of the developed land vertebrates , including the chicken heard by a shore of freshwater living bony fish , which means spawning increased. Between the spawn of the bony fish and today's egg there was an intermediate form of live birth in a placenta. In the course of development, thicker melanin membranes formed around the placenta, the precursors of the shell, which were able to withstand the new environmental conditions on land, but still near the water. Many changes resulted in eggs with shells from spawning. The shell of the amniote eggs protected the embryo from dehydration inland. The question is reduced evolutionarily to the question: What came first: the fish or the spawn? etc. up to the molecular processes that cause the reproduction of living things.

The question arises again in biology in connection with the deciphering of the details of the origin of life in the second half of the 20th century as a prebiotic chicken and egg problem :

Today's life is based both on proteins , which are needed as catalysts for RNA replication, and on RNA, which controls protein synthesis from amino acids . In the simplest cells known today, more than a hundred enzymes (i.e. proteins) are needed for the synthesis of nucleic acids . For protein biosynthesis, the cells in turn need the genetic information that is stored on the DNA . Which of the two types of molecules should have emerged first? Today's life processes cannot do without the simultaneous existence of proteins and nucleic acids.

Today, the RNA world is mostly seen as an elegant explanation. The discovery of the ability of RNA molecules to catalyze other RNA molecules ( Thomas R. Cech , Sidney Altman , Nobel Prize in Chemistry 1989) is of particular importance here. This made it clear that RNA, which has both catalyzing properties like proteins and information-storing abilities like DNA, has the potential for self- replication ; As “all-rounders”, RNA molecules are chicken and egg in one. Such ideas are supported by the discovery of enzyme-free self-replication of short nucleic acids (Kiedrowski, 1986) and several other self-replicating systems (including peptide systems). Here, in turn, replication systems with almost exponential growth are particularly important, since these properties are important for the further evolvability of the systems, ultimately towards cellular life. The discovery that PNA or TNA can be important as possible RNA precursor molecules for the development of the RNA world also supports this idea.

religion

Most religions declare the world to be divine creation . So was until well into the 19th century in the Christian world the story of creation in Genesis 1 (Genesis), by which the canon of the Bible begins, as widely accepted model of the origin of life on Earth. For the Christian churches and most people , God created all kinds of animals and with them the hen. After mating by the first rooster, the hen laid the first egg, from which the first offspring in the form of chicks hatched. With the same reasoning, it was also argued that Adam and Eve probably did not have a navel. A “chicken and egg problem” did not even exist.

Ideas that still cling to this traditional view today are called creationist . Similar lines of argument can also be found today in the Islamic environment when it comes to the reception of scientific knowledge.

In the Jewish and Christian tradition, the question was considered resolved. According to the biblical account of creation, God created fish and birds:

"God blessed them and said: Be fruitful and multiply and populate the water in the sea and the birds should multiply on the land."

- ( Gen 1.22  EU )

This solved the problem only for those who accepted the biblical account of creation. Johann Wolfgang von Goethe mused:

“Was the hen first? or was the egg before the hen? Whoever solves this riddle settles the dispute about God. "

economy

In the economy , the chicken and egg problem stands for the problem that there is neither supply nor demand for some products or services on the market and both have to be created at the same time.

Related topics

  • In programming , a compiler is a program that converts the program code into an executable program. How do you compile the program code for a compiler, but if a compiler is not yet available? This is the so-called bootstrapping problem.
  • A cyclical causal chain with unfavorable effects is known colloquially as a vicious circle .
  • Catch-22 , the title of a novel by Joseph Heller , became the epitome of a quandary in the sense of dilemma .

literature

  • Bruno Heller: Questions of Philosophy 1: Approaches . Books on Demand GmbH, no location, 2000, ISBN 3-8311-0286-4 .

Web links

Individual evidence

  1. ^ Plutarch : Moralia . Table discussions, II, III ( online ).
  2. ↑ Macrobius : Saturnalia . VII, XVI ( online ).
  3. ^ François Fénelon : Abrégé des vies des anciens philosophes . Paris 1726, p. 314 ( online ). English translation: Lives of the ancient philosophers . London 1825, p. 202 ( online ).
  4. ^ Helena Petrovna Blavatsky : Isis unveiled 1 - Science . The Hague 1975, pp. 428f., ISBN 3-89427-244-9 .
  5. ^ Johann Wolfgang von Goethe : Complete edition of the works and writings in twenty-two volumes: Poetic works . Cotta, Stuttgart, no year, p. 878 ( online ).