机き上じょうの空くう論ろん

expression, noun

armchair theory; impractical idea; unworkable plan

Refers to a theory or plan that sounds good on paper but is unrealistic or cannot be implemented in practice. Often used critically.

• 彼かれの提てい案あんは机き上じょうの空くう論ろんに過すぎない。

  His proposal is nothing more than an armchair theory.

• その計けい画かくは机き上じょうの空くう論ろんで終おわった。

  The plan turned out to be an impractical idea.