Sugar Ray's style, as a boxer and as a hip cat about town, represented the vanguard of cool for Miles: As he once said, you've got to have style in whatever you do -- writing, music, painting, fashion, boxing, anything. Some styles are slick and creative and imaginative and innovative, and others aren't. Sugar Ray's style was all of that.'' Cool, for Miles, was about appropriating style from a diverse array of influences, here using the imagery from boxing to influence his trumpet playing, and then putting his own unique spin on it. This was the case with his music -- and in his life.

Cool was also the opposite of the ''Uncle Tom'' posture that had become the expected mode of expression for black men during an earlier time. But Miles would slay the dragon of racial expectations in the very way that he took the bandstand. Often performing with his back to the audience, Miles would eventually stop announcing the title of his songs and avoided making small talk with those in attendance at his gigs while on the bandstand. He was a musician, an artist, not an entertainer. He faced his band like the conductor of a symphony orchestra, but he might as well have been telling the audience to kiss his ''black ass,'' as it were. Why announce the title of the tune when people already knew it?

While such acts of defiant coolness would barely raise an eyebrow now, it was akin to a quiet revolution when Miles did it back in the day. Miles was once a victim of police brutality, after being assaulted by a cop while walking a white female friend to a cab outside Birdland. The fact that Miles' name was on the club's marquee mattered not to the cop that night. Yet despite the obvious dangers associated with his cultural defiance, here was Miles, wearing dark sunglasses, casually holding his horn, displaying his calculated indifference on the album cover of Round About Midnight back in 1957. This upper-middle-class black man, clean as a properly cooked chitlin', stood utterly confident before the conservative forces of white America at a time when many black people in the South still couldn't even get a decent drink of water. He was aloof, indifferent and utterly above it all -- the living personification of cool.

There would come a time when several white musicians on the West Coast would begin appropriating Miles' musical style from Birth of the Cool. This opened the floodgates and before long cool was being poached by the masses.

In the present, as the poignant AMC drama Mad Men assumes its fourth season, one finds a clever cultural rewind to an era that could easily be regarded as the last days of cool; that period in the early 1960s just before America would experience its own version of a cultural revolution. Mad Men reminds us that there was a calm before the storm. The world of Mad Men is one that existed before alcohol-monitoring ankle bracelets, before sexual-harassment training in the workplace, and before the habit of smoking cigarettes made one decidedly uncool. The program's decadence by default seems downright radical at times by contrast, considering the numerous social prohibitions that have arisen in the years following those that frame Mad Men.

Yet, for all of its strengths, Mad Men wouldn't be nearly so appealing if not for the fact that it is set during a time when America was neatly divided between the hip and the square. It's important to point out, though, that during the early '60s, the time period that Mad Men is set, people like Don Draper and his colleagues would most certainly have been regarded as undeniably square. Cats like Draper represented the very meaning of the establishment. There is a scene in the first season when Draper makes an impromptu visit to see one of his many mistresses, only to find her and her friends ''getting high and listening to Miles'' as she plays "Sketches of Spain" on the turntable; an earlier episode in the first season used Miles' ''Blue in Green'' from Kind of Blue. In the scene with ''Sketches'' playing, it is quite obvious that Draper is a first-class square. In addition to supporting Richard Nixon in his 1960 presidential bid against JFK, something else they did in the first season, ad agencies like the fictional Sterling Cooper helped to shape a nation of gullible consumers, who eagerly drank the poisoned Kool-Aid of consumption.

So Mad Men is only cool now because the representation of the era relies on imagery that came to be regarded as cool over time. The clothing styles, the midcentury modern furniture, the retro ads and the three martini lunches seem quite cool in 2010. That being said, it is the cool created and nurtured by someone like Miles Davis that informed both the era in question and the present representation of Mad Men, even when such a cultural phenomena is not necessarily present on screen all the time. The cool of Mad Men owes a debt both to jazz music in general and to Miles Davis specifically.

Jazz is like the unheard soundtrack of Mad Men, as it is for that era, while the spirit of Miles, the patron saint of cool, inhabits the overall vibe that infuses this program with its most compelling sense of style and attitude. Considering that cool has always been elusive and not necessarily visible to the naked eye, it makes sense that such an invisible though highly potent cultural force would inform the coolness that Mad Men inhabits.

Dr. Todd Boyd is the Katherine and Frank Price Endowed Chair for the Study of Race and Popular Culture and professor of critical studies in the USC School of Cinematic Arts. His blog is Notorious Ph.D.

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