Correction Appended

MILES DAVIS'S career began in July 1944, when the legendary Billy Eckstine band visited St. Louis. Booked into a white club aptly named the Plantation, Eckstine was fired for using the front door instead of the ''colored'' rear entrance. So he took his amazing band, which included Charlie (Bird) Parker, John Birks (Dizzy) Gillespie and Art Blakey, to a Negro establishment, the Riviera Club, where they played with fiery beauty before a large, enthusiastic black audience -- and hurled a lightning bolt of inspiration at an 18-year-old trumpeter named Miles Davis.

Years later Davis would confess, ''I've come close to matching the feeling of that night in 1944 in music, when I first heard Diz and Bird, but I've never quite got there.'' A strange statement, coming from a figure so full of musical refulgence. What kind of lightning struck Davis that night? And why did it strike only once?

The answer lies in Davis's lifelong struggle to achieve three goals: high musical art, commercial success and a deep connection with his fellow African-Americans. Are these goals compatible? Not today, perhaps. But they were compatible during Davis's boyhood, when immortals like Armstrong, Ellington and Basie played dance halls and night clubs and, as the saying goes, ''good music was popular and popular music was good.'' And they were compatible on that memorable night in 1944.

The three goals began to conflict during the last 50 years, a time fraught with musical dead ends, distractions and dangers. In the 1950's, jazz ceased to be entertainment and became esoteric art. In the 1960's, rock and soul won a huge racially mixed audience and cultural cachet, only to succumb a few years later to racial polarization and the decadence of heavy metal and disco. Also in the 1960's, the art music known as minimalism inspired a rejection of song and dance that over the next three decades would help (inadvertently) subordinate the aural to the visual, the ear to the eye. In the 1970's punk restored the cachet of rock but also turned it into avant-garde theater. And in the 1980's, hip-hop revived rhythm but also fostered the myth that truly ''black'' music does not utilize melody or harmony.

When Davis first apprenticed himself to Parker and Gillespie in the mid-40's, be-bop was popular in Harlem. But as be-bop grew more virtuosic, many black listeners sought the simpler pleasures of rhythm-and-blues, leaving a core of loyal fans but no reliable market niche. Among whites, be-bop attracted discerning admirers but also undiscerning thrill seekers. Add the ravages of heroin, the death of Parker and the condescension of the mainstream, and one can see why Davis's career almost ended in the early 1950's.

But then he landed on his feet, creating (with Gil Evans) the new sound of cool. Critics still debate the virtues of cool: Max Harrison praises its ''muted colors'' and ''lucid proportions''; Stanley Crouch dismisses it as ''another failed attempt to marry jazz to European devices.'' Yet everyone agrees that cool was a hit with whites -- especially ''Kind of Blue'' (1959), whose mass appeal would today place it next to the chai tea in Starbuck's.

As cool grew ''whiter'' in the hands of West Coast musicians like Dave Brubeck, Paul Desmond and Chet Baker, the dense percussive style known as hard bop became the ''black'' alternative. Yet this racial divide did not affect Davis, because as Gary Giddins notes, ''The warring subcultures, West Coast jazz (cool) and East Coast jazz (hard bop) had the same Midwestern parent: one Miles Dewey Davis.'' To the yin of cool, Davis brought rich sonority, blues feeling and swing; to the yang of hard bop, he brought stillness, melodic beauty and understatement. By refusing to color-code either his music or his audience, he rose at the age of 34 to the summit of artistic excellence.

Next came the upheavals of the 1960's. The first was in jazz. Since the 1930's, jazz musicians had been exploiting such modernist ideas as chromatic harmony, modal scales and electronics. But in the 1960's the New Thing, led by Ornette Coleman, John Coltrane and Cecil Taylor, went further: expanding the sound vocabulary of instruments, eliminating cadential harmony and the modal system, exploring polytonality and atonality, adopting irregular meter, and finally abolishing metric time. The goal, turbo-boosted by black political activism, was total improvisatory freedom.

Some jazz elders were dismayed. Coleman Hawkins growled in 1964: ''Those guys are looking for a gimmick, a short cut. There is no short cut.'' And Davis himself quipped that if Taylor was ''what the critics are digging,'' then ''them critics better stop having coffee.'' But here again, Davis landed on his feet. With four fiercely gifted young players -- Ron Carter, Herbie Hancock, Wayne Shorter and Tony Williams -- he set off a controlled explosion that equaled the excitement of the New Thing but that took a disciplined route brooking no short cuts.

It would have been the perfect solution had Davis not noticed that jazz was being eclipsed by rock. Never one to assume that ''the fewer hear you, the better you are,'' he gravitated to where the action was -- to countercultural icons like Jimi Hendrix and Sly Stone -- and made his famous 1969 ''jazz-rock fusion'' album, ''Bitches Brew.''