Urban Legends

Boiling frog

The boiling frog is an describing a slowly being . The premise is that if a frog is placed in boiling water, it will jump out, but if it is placed in cold water that is slowly heated, it will not perceive the danger and will be cooked to death. The story is often used as a for the inability or unwillingness of people to react to threats that occur gradually, such as creeping state surveillance.

According to contemporary biologists, the premise of the story is false: a frog submerged and gradually heated will jump out. However, some 19th-century experiments suggested that the underlying premise is true, provided the heating is sufficiently gradual.

The story's common use is a caution for people to be aware of even gradual change lest they suffer eventual undesirable consequences.

The science[]

Boiling a Frog Without His Knowing It

As part of advancing science, several experiments observing the reaction of frogs to slowly heated water took place in the 19th century. In 1869, while doing experiments searching for the location of the soul, German physiologist demonstrated that a frog that has had its removed will remain in slowly heated water, but an intact frog attempted to escape the water when it reached 25 °C.

Other experiments showed that frogs did not attempt to escape gradually heated water. An 1872 experiment by Heinzmann demonstrated that a normal frog would not attempt to escape if the water was heated slowly enough, which was corroborated in 1875 by Fratscher.

Goltz raised the temperature of the water from 17.5 °C to 56 °C in about ten minutes, or 3.8 °C per minute, in his experiment which prompted normal frogs to attempt to escape, whereas Heinzmann heated the frogs over the course of 90 minutes from about 21 °C to 37.5 °C, a rate of less than 0.2 °C per minute. In "On the Variation of Reflex Excitability in the Frog induced by changes of Temperature" (1882) writes: "in one experiment by Scripture the temperature was raised at a rate of 0.002°C per second, and the frog was found dead at the end of 2½ hours without having moved."

In 1888 Sedgwick explained the apparent contradiction between the results of these experiments as a consequence of different heating rates used in the experiments: "The truth appears to be that if the heating be sufficiently gradual, no reflex movements will be produced even in the normal frog; if it be more rapid, yet take place at such a rate as to be fairly called 'gradual', it will not secure the repose of the normal frog under any circumstances".

Modern sources tend to dispute that the phenomenon is real. In 1995, Professor , of the Biology department, said, "If you put a frog in boiling water, it won't jump out. It will die. If you put it in cold water, it will jump before it gets hot—they don't sit still for you." Dr. George R. Zug, curator of reptiles and amphibians at the , also rejected the suggestion, saying that "If a frog had a means of getting out, it certainly would get out."

In 2002 Dr. Victor H. Hutchison, Professor Emeritus of Zoology at the , with a research interest in thermal relations of amphibians, said that "The legend is entirely incorrect!". He described how the for many frog species has been determined by contemporary research experiments: as the water is heated by about 2 °F, or 1.1 °C, per minute, the frog becomes increasingly active as it tries to escape, and eventually jumps out if the container allows it.

None of these modern rebuttals – Melton, Zug, or Hutchison's – attempts to replicate an extremely slow-heating experiment as cited by Goltz or Scripture: only Hutchison did a thermal trial at over five times Goltz's slow rate and over nine times Scripture's 0.002 °C per second temperature rise.

Use[] As metaphor[]

If you drop a frog in a pot of boiling water, it will of course frantically try to clamber out. But if you place it gently in a pot of tepid water and turn the heat on low, it will float there quite placidly. As the water gradually heats up, the frog will sink into a tranquil stupor, exactly like one of us in a hot bath, and before long, with a smile on its face, it will unresistingly allow itself to be boiled to death.

Version of the story from 's

The boiling frog story is generally offered as a cautioning people to be aware of even gradual change lest they suffer eventual undesirable consequences. It may be invoked in support of a argument as a caution against . It is also used in business to reinforce that change needs to be gradual to be accepted. Oppositely, the expression "boiling frog syndrome" is sometimes used as shorthand to invoke the pitfalls of standing pat.

The story has been retold many times and used to illustrate widely varying viewpoints. Among them: in 1960 about sympathy towards the during the ; in 1980 about the impending collapse of civilization anticipated by ; in the 1990s about inaction in response to and staying in . It has also been used by to warn about slow erosion of .

In the 1996 novel , environmentalist author spends a chapter on the metaphor of the boiling frog, using it to describe human history, population growth and food surplus. 's character Harry Dalton mentioned it in the 1997 disaster movie in reference to the accumulating warning signs of the volcano's reawakening. used a version of the story in his presentations and the 2006 movie to describe ignorance about . In his version the frog is rescued before it is harmed. This use of the story was referenced ironically by writer/director in the title of his 2010 comedic documentary .

Law professor and legal commentator commented in 2003 that regardless of the behavior of real frogs, the boiling frog story is useful as a , comparing it to the metaphor of an with its . Economics Nobel laureate and New York Times writer used the story as a metaphor in a July 2009 column, while pointing out that real frogs behave differently. Journalist has been advocating since 2006 for people to stop retelling the story, describing it as a "stupid canard" and a "myth". But following Krugman's column, he declared "peace on the boiled frog front" and said that using the story is fine as long as you point out it's not literally true.

Inphilosophy[]

In the boiling frog story has been used as a way of explaining the . It describes a hypothetical heap of sand from which individual grains are removed one at a time, and asks if there is a specific point when it can no longer be defined as a heap.