A mediator can compare offers without revealing them

Evidence

A mediator can consummate certain communications while blocking off certain facilities for memory. (In this regard he serves a function that can be reproduced by a computing machine.) He can, for example, compare two parties’ offers to each other, declaring whether or not the offers are compatible without revealing the actual offers. He is a scanning device that can suppress part of the information put into it. He makes possible certain limited comparisons that are beyond the mental powers of the participants, since no player can persuasively commit himself to forget something. — Thomas C. Schelling, The Strategy of Conflict, 335

Categorization

• XREF: The mediator-as-information-suppressing-device is the arbitration function of the private judge — trust requires a party who can hold secrets in ways participants cannot credibly self-impose.