Payment Confidentiality: from the 18th  Century to the Digital Euro

This paper suggests an objective approach to the issue of payment confidentiality. In the 18^th century, this question was simply seen from a criminal perspective. Later attempts to link it to company security, or to propose cryptographic solutions, proved inadequate. When retail banking discovered how to make money on operational data, payment confidentiality was finally defined as protecting databases for consumers and investors. The confidentiality issues raised by the digital euro project are examined from this perspective, as well as from a microeconomic point of view.