a group of reporters approached the general with the request that perhaps he might give them one of several immutable economic truisms that he had gathered from his long years of economic study...
This brought its use and the idea into mainstream popularity.
In the sciences, TANSTAAFL means that the universe as a whole is ultimately a closed system.
"There ain't no such thing as a free lunch" (alternatively, "There is no such thing as a free lunch" or other variants) is a popular adage communicating the idea that it is impossible to get something for nothing.
The acronyms TANSTAAFL, TINSTAAFL, and TNSTAAFL, are also used.
TANSTAAFL, on the other hand, indicates an acknowledgement that in reality 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, although that may be a hidden cost or an externality.
In 1945, "There ain't no such thing as a free lunch" appeared in the Columbia Law Review, and "there is no free lunch" appeared in a 1942 article in the Oelwein Daily Register (in a quote attributed to economist Harley L. The 19 sources use the phrase in relating a fable about a king (Nebuchadnezzar in Dos Utt's retelling) seeking advice from his economic advisors.
Morrow's retelling, which claims to derive from an earlier editorial reported to be non-existent, but closely follows the story as related in the earlier article in the El Paso Herald-Post, differs from Dos Utt's in that the ruler asks for ever-simplified advice following their original "eighty-seven volumes of six hundred pages" as opposed to a simple failure to agree on "any major remedy".
It was the institution of the "free lunch" I had struck.
You paid for a drink and got as much as you wanted to eat.
(See Free rider problem and Tragedy of the commons).