Bach's Numbers : Cambridge University Press : 9781107459694 : 1107459699 : 10 Jun 2016 : In eighteenth-century Germany the universal harmony of God's creation and the perfection of its proportions still held philosophical, moral and devotional significance. Reproducing proportions close to the unity (1:1) across compositions could render them beautiful, perfect and even eternal. Using the principles of her groundbreaking theory of proportional parallelism and the latest source study research, Ruth Tatlow reveals how Bach used the number of bars to create numerical perfection across his published collections, and explains why he did so. The first part of the book shows the wide-ranging application of belief in the unity, demonstrating how planning a perfect structure was a normal compositional procedure in Bach's time. In the second part Tatlow presents practical demonstrations of this in all Bach's publications and fair copies, showing that layers of proportion can appear within a move