No such thing as a free lunch

This article is about an acronym for the adage "There Ain't No Such Thing As A Free Lunch". For No-free-lunch theorem, see No such thing as a free lunch (disambiguation).

TANSTAAFL is an acronym for the adage "There Ain't No Such Thing As A Free Lunch," popularized by science fiction writer Robert A. Heinlein in his 1966 novel The Moon Is a Harsh Mistress, which discusses the problems caused by not considering the eventual outcome of an unbalanced economy. This phrase and book are popular with libertarians and economics textbooks. In order to avoid a double negative or usage of the the word "ain't", the acronym "TINSTAAFL" is sometimes used instead, meaning "There Is No Such Thing As A Free Lunch".

The phrase refers to the once-common tradition of saloons in the United States providing a "free" lunch to patrons, who were required to buy at least one drink.

Details

TANSTAAFL means that a person or a society cannot get something for nothing. Even if something appears to be free, there is always a cost to the person or to society as a whole even though that cost may be hidden or distributed. [1] For example, you may get complimentary food at a bar during "happy hour," but the bar owner bears the expense of your meal and will attempt to recover that expense somehow.

It is thought that TANSTAAFL may not always hold at the individual level, depending on the interpretation of the phrase; for example, some may argue that mothers provide their breast-fed children with milk at no cost. But the mother in turn had to consume food to generate the milk, and this food had to be produced by someone somewhere. Even though the cost is not paid by the children themselves, it is still paid by someone. Indeed, it might be argued that the mother's body pays the cost of the child's meal (or even the plants or animals whose lives were sacrificed to nourish the mother). It can be argued though that the mother might have consumed the same amount of food anyway, meaning that the only difference to her would be that her body mass and nutritional level might be different in ways that wouldn't affect her well-being, which would make the example with the mothers milk a bad one.

Hence, it seems that if one individual is getting something at no cost, somebody else ends up paying for it. If there appears to be no direct cost to any single individual, there is a social cost. Similarly, someone can benefit for "free" from an externality or from a public good, but someone has to pay the cost of producing these benefits.

The idea that there is no free lunch at the societal level applies only when all resources are being used completely and appropriately, i.e., when economic efficiency prevails. But when inefficiency exists, one can get a "free lunch". For example, microeconomics argues that the production of pollution may be inefficient because the polluters are not forced to pay for the damage they cause. A tax or other program that forces the polluter to internalize this externality would improve efficiency, increasing social welfare. In practice, however, others who are benefiting from the inefficiency will use their political power or social power to prevent this tax. That is, the polluter may use lobbying and campaign contributions to preserve his or her ability to freely pollute.

Also, one can obtain a free lunch of fruit picked in the wilderness; and it may be public policy that such fruit is freely available for anyone to pick.

To a scientist, TANSTAAFL means that the system is ultimately closed — there is no magic source of matter, energy, light, or indeed lunch, that cannot be eventually exhausted. Therefore the TANSTAAFL argument may also be applied to natural physical processes. (See Thermodynamics.)

In mathematical finance, the term is also used as an informal synonym for the principle of no-arbitrage. This principle states that a combination of securities that has the same cash flows as another security must have the same net price.

TANSTAAFL is sometimes used as a response to claims of the virtues of free software. Supporters of free software often counter that the use of the term "free" in this context is primarily a reference to a lack of constraint rather than a lack of cost.

TANSTAAFL is the name of the student-run snack bar in the Pierce residential student dorm of the University of Chicago. The name references the fact that the use of the term in economics was popularized by Milton Friedman, the Nobel Prize–winning former University of Chicago professor.

Citations

• In 1950, a New York Times columnist ascribed the phrase to economist Leonard P. Ayres of the Cleveland Trust Company. "It seems that shortly before the General's death [in 1946]... a group of reporters approached the general with the request that perhaps he might give them one of several immutable economic truisms which he had gathered from his long years of economic study... 'It is an immutable economic fact,' said the general, 'that there is no such thing as a free lunch.'"
• "Oh, 'tanstaafl'. Means 'There ain't no such thing as a free lunch.' And isn't," I added, pointing to a FREE LUNCH sign across room, "or these drinks would cost half as much. Was reminding her that anything free costs twice as much in the long run or turns out worthless."
  • Manuel in The Moon Is a Harsh Mistress (1966), chapter 11, p. 162, by Robert A. Heinlein
• "There's no such thing as a free lunch."
  • popularized by economist Milton Friedman;
  • Contrary to rumor, New York Mayor Fiorello LaGuardia did not say it in Latin in 1934; what he really said, in Italian, was "No more free lunch" (current references: linguistlist and a speech by George H. W. Bush; more references needed).
• The book TANSTAAFL, the economic strategy for environmental crisis, by Edwin G. Dolan (Holt, Rinehart and Winston, 1971, ISBN 0-03-086315-5) may be the first published use of the term in the economics literature.
• Malcolm Fraser, prime minister of Australia, was a fond user of this phrase .
• Spider Robinson's 2001 book 'The Free Lunch' draws its name from the TANSTAAFL concept.

See also

• Free lunch
• No free lunch in search and optimization
• No-arbitrage bounds
• Parable of the broken window
• Tanstagi

References

TANSTAAFL is used by Larry Niven, in Ringworld.