Assume a can opener

"Assume a can opener" is a catchphrase used to mock economists and other theorists who base their conclusions on unjustified or oversimplified assumptions.

[3] The first book mentioning it is likely Economics as a Science (1970) by Kenneth E. Boulding:[4] There is a story that has been going around about a physicist, a chemist, and an economist who were stranded on a desert island with no implements and a can of food.

"[10] US President Ronald Reagan told the joke to students and faculty at Purdue University on April 9, 1987, saying: "It seems an economist, a chemist, and an engineer were stranded on a desert island.

'"[11] Italian finance minister Tommaso Padoa-Schioppa used the phrase in 2006 to illustrate that "Very often, when economists comment, they assume politics away.

"[12] It has been used in Australia to describe "a treasurer who has lost all touch with reality"[13][opinion] and politicians "assuming away" the problem of getting a global greenhouse gas deal.