Text: In providing services and in establishing classifications, rates, and fees under this title, the Postal Service shall not, except as specifically authorized in this title, make any undue or unreasonable discrimination among users of the mails, nor shall it grant any undue or unreasonable preferences to any such user.
Entailment: The Postal Service shall not make discrimination among users of the mails under this title.
Contradiction: Discrimination is preferred by the Postal Service.