As part of research for a forthcoming Tax Foundation piece, I came across this gem of definitional tautology: Internal Revenue Code Sec. 141(b): (6) PRIVATE BUSINESS USE DEFINED.– (A) IN GENERAL—For purposes of this subsection, the term “private business use” means use (directly or indirectly) in a trade or business carried on by a person other than a governmental unit.[…] (7) GOVERNMENT USE DEFINED.–The term “governmental use” means any use other than a private business use. So, private use is defined as everything but a government use, and government use is defined as everything but a private use. Useful!