Abstract
This is the first of three publications on the function of René Descartes’ concepts of the «method» and of the «order» in the system of French Baroque organ art that unites the organ building, the composer’s work and the interpretation. As a result of comparative analysis of Renaissance and Baroque organ specifications the new rational principles of the French organ building at the turn of the 16th–17th centuries are revealed and the early Baroque «specification-type» relevant to the «method» and the «order» criterions is reconstructed.