One way to trace the creative footsteps of a great composer is to look at his total output; another approach is to consider all the works in a given genre. 　　Assessing the cycle of Beethoven's 16 string quartets or his 32 piano sonatas, for example, offers a convenient summary of the composer's creative evolution—his so-called "early," "middle" and "late" styles. The 10 glorious sonatas in this collection, however, yield a more truncated autobiographical portrait for the obvious reason that none of them was composed after 1812. But what they do tell us about the man and his music is no less important for that skewed emphasis. 　　The very fact that all but the last two of these sonatas were composed in groups may well explain their wonderfully diverse character and style: as a rule, when Beethoven sent a group of works of the same genre to one of his publishers (and sometimes to several at the same time to see which offered him the best price), he usually felt obliged to make each a strongly characterized entity. Thus, in the three sonatas of both Op. 12 (c. 1798) and Op.30 (1802), we find that each set includes a work of grand scale (the E-Flat Sonata, Op.12 No.3; the C Minor Sonata, 0p.30 No.2), one of essentially lyric character (the A Major, Op.12 No.2 and the A Major, 0p.30 No.l) and one that defies easy classification (the First Sonata, Op.12 No.l, and the Eighth, Op.30 No.3, neither big works, but both demanding technically and having more than a modicum of Beethovenian dynamism). Similarly, the Sonata in A Minor, Op.23 and the "Spring" Sonata, Op.24, were composed in close order—1800 and 1801, respectively—and have something in common: a thematic similarity between Op.23's second movement and Op.24's "off-beat" Scherzo and the fact that both movements were later echoed by Robert Schumann in his "Soldiers' March" from the Album for the Young. 　　For whatever reason, there is a high preponderance of the theme-and-variation form, which Beethoven uses no less than four times in the course of these 10 sonatas (as opposed to only five times in the 32 for piano). In Op.12 No.l and the "Kreutzer" it serves as the slow movement; in 0p.30 No.l and the more innovative Op.96, however, it is the basis for the finales. 　　Much can also be learned about Beethoven's development by placing these sonatas into their proper chronological context: one immediately discovers the close relationship between the last movement of the "Spring" Sonata and its counterpart in the Op.22 Piano Sonata. One can, likewise, discover the kinship between the C Minor Sonata, 0p.30 No.2, and Beethoven's other Sturm und Drang C minor works: the Piano Trio, Op. 1 No.3, the Piano Sonata, Op. 10 No. 1, and the Quartet, Op. 18 No.4, being prime examples. Similarly, one can better appreciate both the G Major Sonata, 0p.30 No.3, and the Piano Sonata, Op.31, No.3, by listening to their highspirited antics in the context of each other; so too, better insight into the composer's lyric diversity can be gained by putting the Tenth Sonata, Op.96, alongside the Fourth Piano Concerto, the Violin Concerto and the "Archduke" Trio. 　　Each of these sonatas appears to be a perfectly constructed entity, with the various individual movements creating a masterful balance between architecture and emotion. But that may well be a deceptive—and reflexive—impression: it is rather sobering to discover that Beethoven at one point had actually considered using the brilliant, incendiary finale of his "Kreutzer" Sonata as the last movement of the 0p.30 No.l (a context that seems jarringly incongruous). 　　Following the conventions put forth by his great predecessor Mozart, Beethoven designated these sonatas as "for piano and violin," but in spite of this sometimes heatedly defended nomenclature, a full equality exists between the two protagonists. This equality is evident at all times—whether one considers the brilliantly virtuosic "Kreutzer" (where both instruments are required to play in "con-certante style") or any of the other sonatas. Jascha Heifetz may, in the public's mind, have epitomized the bravura virtuoso violinist, but his art (happily bequeathed to us on recordings) is of the purest classicism. One hears in this cycle of the 10 Beethoven sonatas an awareness of—and concern for—a true musical dialogue; an exchange in which the violinist's brilliance and refinement are handsomely echoed by his elegant collaborators, Emanuel Bay and (in the "Kreutzer") Brooks Smith.