The stylistic homogeneity of 18th-century music poses difficulties when one tries to assert resemblances between themes. Unless we can demonstrate that the composer expressly intended for there to be a specific thematic connection between his music and another piece, our claims of a definite resemblance between two Classical themes are usually greeted with considerable skepticism. When faced with a lack of concrete biographical evidence, we should therefore subject the themes to a rigorous screening process before we can reasonably assert that one theme consciously resembles another. The first criterion is statistical background: while the resemblance between two themes A and B might be striking, if it can be shown that there are also several other themes that equally resemble A and B then the significance of the original relationship is greatly reduced. The second criterion is structural similarity, which must consider at least three aspects: (1) melodic contour; (2) rhythmic function; and (3) tonal and harmonic background. This screening process is put to the test in works by J. S. Bach, J. C. Bach and Haydn, proving that seeming thematic resemblances between works or between movements of the same work are coincidental. The article concludes with examples from two symphonies--one by Rosetti (DTB XII/I) and Haydn's Symphony No. 103--in which a thematic resemblance between a slow introduction and the following fast movement is strong enough to assert a definite intent on the part of the composer.

Works: Haydn: Symphony No. 103 (234); Francesco Antonio Rosetti: Sinfonia in Dis (234).

Index Classifications: 1700s

Contributed by: Mark S. Spicer