Tchaikovky's First Piano Concerto is one of those enduring works that ignore reason. It may lack nobility of thought, as has been asserted, and it probably is structurally weak. But when that introductory theme sounds in the orchestra and the piano enters with its crashing chords, even the most stern musicologist should be unable to resist.

The listener was far from being swept away, however, when pianist Alexis Weissenberg and the Boston Symphone under Seiji Ozawa started in on the concerto Saturday night at the Kennedy Center. A horn flub in the first measure hit like a sudden cold draft. Then Weissenberg began moving up and down the piano in a precise, deliberate manner which did nothing to raise the temperature. And so it went through most of the concerto.

Though free from error, most of the orchestral solos were given an uninspired reading, and Weissenberg continued with his careful, thoughtful performance. Ozawa faithfully followed his lead, keeping a restrained hand on the orchestra. There were beautifully phrased exchanges between the piano and orchestra and tasteful playing from Weissenberg. What one missed was excitement, that brilliance and intensity which make the concerto's emotional side come to life.

It was another orchestra which performed Tchaikovsky's Sixth Symphony after intermission. From the opening bassoon passage on, solos were lovely and the orchestra's sound richly expressive, as the players responded with dazzling quickness to Ozawa's dramatically sure pacing of each movement.