According to late American critic Susan Sontag, dancers live by the “standard of perfection.”

“Dance demands a degree of service greater than in any other performing art, or sport,” she wrote in her 1987 book “Dancers and the Dance.”

“While the daily life of every dancer is a full-time struggle against fatigue, strain, natural physical limitations and those due to injuries (which are inevitable), dance itself is the enactment of an energy which must seem, in all respects, untrammeled, effortless, masterful and at every moment fully mastered.”

Famed ballerina Kang Sue-jin is a living example of just that. The 45-year-old’s performances have been, in Sontag’s words, a “creation of illusion”: the illusion of a weightless body, a body without fatigue, and a body that transcends its limits. Seo Hee, the Korean-born principal dancer of the American Ballet Theater, calls Kang “someone so great I cannot dare compare myself to.”

For the last few decades, the long-time principal of Germany’s Stuttgart Ballet has been an icon of hard work, diligence and rare beauty in her home country. The famous photograph of her bare feet, severely scarred and calloused, showed what it takes to appear “effortless and masterful” on stage.

The dancer recently published her first memoir, “I Don’t Wait for Tomorrow.” The Korean-language book reflects her life philosophy, which can be summarized by the Latin phrase “carpe diem,” or “seize the day.” The dancer is also famous for her life offstage, which is rather simple and monotonous. She has not missed a single day of practice in the last 30 years of her career.

Her daily routine consists of morning coffee and sauna, eight to nine hours of practice, dinner and sleep. Both on and off stage, she tries to project a state of total concentration ― in her effort to live each day to the fullest.

“I never really dreamed of becoming a prima ballerina,” the dancer said in a group interview with the local press at JW Marriott Hotel in southern Seoul on Tuesday.

“I don’t really set big goals in life. I just liked each day’s practice, and enjoyed seeing myself improving. And even if you hold a title of prima ballerina, you are not really one unless the audience approves you as one. I find people’s recognition more important than titles.”

Even as a child, Kang didn’t dream of anything big.

“I think I was the happiest when I ate kimchi and rice with my family,” she said. “Things were much simpler back in the 1970s. My family lived in a hanok (traditional Korean house). We had a TV. We felt like we had enough. I had a very happy childhood. My parents never forced me into something that I didn’t like to do. And I didn’t really dream of becoming anything, really.”

Her simple life met its end when she was introduced to the world of ballet while attending middle school. Kang decided to move to Europe alone at age 13 for ballet training in Monaco.

“You know, that’s what’s great about being young,” she said. “You become brave because you just don’t know much. I don’t really think I had any idea about what it means to live in a foreign country on your own.”

Kang joined the Stuttgart Ballet at 17. At the time, she lived in a cold, damp basement studio, with mold on the wall. Her life as the troupe’s youngest member was lonely and far from easy. Every day, she would spend 18 hours in the dance studio, in the hope of improving her skills and becoming a better dancer.

“I was completely miserable at the time,” she said. “The winters were very cold. Sometimes it would be minus 20 degrees. The sky was always dark and gray. I had a hard time getting myself up every morning, because I simply did not want to go outside. Dragging myself to the dance studio was the hardest part.”

A dancer’s performance smile, Sontag said, is “not so much a smile as simply a categorical denial of what she is actually experiencing,” for there is “some discomfort, and often pain, in every major stint of performing.”

Kang said her life, every single moment of it, was inseparable from pain.

“I just think of it as my companion who is with me all the time,” she said. “You cannot be a dancer without being in pain. That’s just impossible.”

In her book, Kang writes that a total state of concentration comes from “being crazy about something.” Her life has been all about ballet, except her happy marriage with her former dancing colleague Tunchi Shockman.

“I always think about ballet, on and off stage, every single day of my life,” she writes in the book. “When you are dancing and completely immersed in your role, you cannot feel the presence of the audience. I’m totally crazy about ballet.”

Her memoir also offers a number of life tips, on eating well, forming relationships with others, and appreciating all forms of art. Kang firmly believes one can only get better at something by repetition and training.

“I didn’t write this book just for dancers,” she said. “It’s about how to focus on your present and be the person you want to be.”

By Claire Lee dyc@heraldcorp.com">(dyc@heraldcorp.com)