It came as a shock of delight while reading “Yojokun: Life Lessons from a Samurai” (Kodansha, $19.95), a work of classical Japanese philosophy, to realize that what I held in my hands was a self-help book. A self-help book of rare charm and elegance, but a self-help book nonetheless.

As translator William Scott Wilson notes in his introduction, the thrust of this book “is not medicines and cures, but a lifestyle that prevents the onset of disease.”

The author, Kaibara Ekiken (1630-1714), was a samurai physician, botanist and neo-Confucian philosopher who wrote many books and is credited with introducing empirical science to Japan.

When he collected his notes on health and happiness at age 84, Ekiken went against tradition by writing in simple, accessible language. He wanted his precepts to reach not only the samurai and educated classes, but poor working people, too. Nearly 400 years later, it remains a widely read health manual in Japan.

Ekiken, who calls long life the primary source of human happiness, believed that every person is born with the potential of living to 100. It is only by following immoderate habits that we thwart our natural vigor and die before our time.

“Indeed,” Ekiken writes, “to consider the gift of life as your possession alone and then to abuse it by overindulging in food, drink, sex, or in any other manner is to squander your health and invite disease.”

Much of Ekiken’s advice seems contemporary. Eat, drink and exercise moderately. Discipline the mind and emotions. Avoid too much anxiety, depression or joy: “Overindulging your desires and damaging your body is the same as taking up a sword and killing yourself.”

Ekiken writes of sleep as though it were an addiction, saying, “The habit of sleeping less is something to which you should apply yourself.”

For the most part, though, Yojokun may be read as a useful compendium of sensible advice on sustaining health and longevity. Ekiken even includes lists of moderate behavior and eating habits for the elderly, warning against “highly spiced foods even if they taste good.”

The title, “Yojokun,” means “Lessons on Nurturing Life.” Ekiken’s notion that health includes emotional, mental and spiritual components is what today we would call “holistic.” What could be more modern?