In 1961 Pablo Casals, the world-famous cellist, said of a student, "I have taught him everything I know." Tuesday night that same student, Takeichiro Hirai, taught an audience at the Kennedy Center Terrace Theater something about cello playing too.

Skillfully accompanied by Washington pianist Betty Bullock, Hirai played with great clarity of line and precision of phrase. Both qualities are unquestionable strengths. But as his playing demonstrated and the audience heard more than once, these virtues do not in themselves make great performances.

The faster sections of Vivaldi's Cello Sonata No. 5 in E Minor, the slender Beethoven Variations on "Bei Maennern, welche Liebe fuehlen," and Mendelssohn's Sonata No. 2 in D, Op. 58, were let down by playing that was sober, even glum. Hardly a trace of real, robust warmth could be heard in any of them.

Fortunately Hirai rallied superbly in the remaining selections. Both in the Largo sections of the Vivaldi, where his cello spoke with a sad and poignant elegance, and in the pizzicato movement of his own "Latina" Suite for Solo Cello, with its teeming double-stops, Hirai demonstrated the complementary fire to his earlier ice.

The three pieces in the closing Schumann "Fantasiestuecke," Op. 73, were splendid. Wistful in the first, elegiac in the second and impassioned in the third, Hirai's playing couldn't have been better, or his accompaniment more sensitive.