The Art of Fugue is a collection of compositions in an austere contrapuntal style, all of which are based on the same subject. The latest research on the score reveals that Bach started this copious work around 1742 2. However, it is known that the first edition was published in 1751 3. Today, many different sources of the score exist, primarily including the autograph manuscript P200 and a limited series of copies of the first and second original editions of 1751 and 1752, respectively 4. Over time, many unsettled issues have continued to vex scholars and musicians. These issues can be summarised as follows: a. The explanation of the differences in the music score between manuscript P200 and the original edition. b. The ordering of the composition. c. The instrumentation of the work.