"Glue painting?" Rather unattractive.

"Japanese single-style paintings of the modern era?" Rather limiting.

Scholars have always had a hard time defining nihonga, but recognizing this style of art is a bit like true love: You know it when it comes along. If you are not familiar with this national art form, then a visit to "Nihonga of the 20th Century" at the new Geidai Museum will be an enjoyable introduction. If you are already enamored, you will not want to miss this overview, and the first-class paintings by past and present masters.

Before modernization, there was no such thing as nihonga. For hundreds of years, there had been various schools or styles of Japanese art, following fairly rigid rules, and evolving like corals in the warm waters of tradition. The opening of the country to the West at the end of the Tokugawa Period, however, let in a flood of new ideas. Influential scholars such as Ernest Fenollosa and Tenshin Okakura were greatly concerned lest native art be overwhelmed.

Fenollosa used the term "nihonga" in 1882, to describe the need for a new national art. In the convulsive years that followed, a fierce debate raged about nihonga versus yoga, the bewitching style of oil painting fresh from the West.

At the heart of the conflict was the country's first national fine arts academy, opened in 1889, now the Tokyo National University of Fine Arts and Music, known to all as Geidai. At first, the academy taught Japanese painting only, but opened a department of Western art amid much controversy in 1896. Although the two are still taught as separate subjects, students have been borrowing from each other's conventions for over 100 years.

Many of the country's finest artists have been professors or graduates of the university, which has built up an important collection over the years. The current exhibition features historic paintings from the archives and important works from the National Museum of Modern Art (whose main building is currently closed for a major refurbishment).

So nihonga is the 20th-century fusion of 1,000 years of Japanese culture, fanned by winds from the West. Given its complex pedigree, some experts wonder if foreigners can appreciate its finer points. Of course, understanding the context helps enormously, but the world's great paintings are not required to be intellectual, and nihonga, especially, speaks directly to the heart. Like a Zen master, the best of these artists can strip away irrelevance to reveal simple, lasting truths. All we have to do is open our minds.

The first striking thing is the great variety within this single genre. Here are lyrical landscapes, naive paintings of bright tropical scenes, and decorative screens of spring and autumn in the gorgeous Rinpa style, given a modern twist. The list could go on, but the first gallery alone is packed with interest.

Here, we can see artists exploring the mists and lines of traditional painting in colorful new ways. For example, Seison Maeda's superb guardian deity "Ashura" is a traditional subject handled with the vivacity of a manga. Look at those virile lines sweeping through the figure and the confident use of "wet in wet" technique, with paint drizzled onto damp paper for the textures of leather and stone.

Traditional hanging or rolling scrolls were rapidly replaced by paintings mounted in frames, like Western oils. No doubt this was more convenient for displaying in galleries and modern homes, but even pioneering artists had an understandable affection for painting on scrolls.

Two of nihonga's first sons were Kanzan Shimomura and Taikan Yokoyama. Both artists experimented with hazy, soft-line brushwork at the beginning of the century, but in his narrative scroll of a scene from the "Tale of Heike," Shimomura turns again to the crisp classical style. The scroll depicts the visit of the ex-Emperor Go-Shirakawa to the lonely temple at Ohara, where Kenreimon'in, the bereaved mother of the child Emperor Antoku, has gone to end her days as a nun. This is a lovely mountain, beyond Kyoto, which even today feels like a retreat from the world.

In limpid colors, and clear detail, the artist depicts the spring scenery and evokes a melancholy atmosphere. Kenreimon'in, catching a glimpse of her visitors, looks reluctant to descend from the mountainside with her basket of wild azaleas. As the tale says, "she would gladly have hidden herself somewhere to avoid them."

But she is persuaded to meet her kinsman in the tumbledown hut, where "the rain, the hoarfrost, and the dew of evening vied with the moonbeams in gaining entrance" through the broken roof. The final scene is the moon glimmering through the pines.

Altogether different is Yokoyama's masterpiece in ink, "Metempsychosis," painted in 1923. Here, the Eastern philosophy of ever-changing existence is pictured as dew forming into a mountain stream and traveling toward the sea. We cannot see the whole scroll at once, as it is nearly 5 meters long! But whatever section is on display, whether monkeys by a waterfall, cormorants by the shore, or the final metamorphosis of ethereal waves and dragon, one can only marvel at such a combination of insight and skill.

Another highlight is Cho Ota's large canvas of young women gazing at the stars. His paintings of elegant young ladies of the 1930s are in the decorative tradition of bijin-ga. His composition is superb (look at the dramatic way the telescope slices across the scene, all but hiding one of the girls) and his lines are ravishing. More than these details, though, the whole painting is a moving evocation of beauty in touch with eternity.

It seems to me that this sums up the silent language of the art. Whereas many a Western painter has tackled the same subject and loaded his canvas with symbolism, the Eastern artist can put his finger on the point with the lightest, truest touch.

Perhaps you will find this spiritual dimension in many other paintings in the exhibition, such as the charred, calligraphic intensity of Misao Yokoyama's burned-out tower, or the deep blue and gold textures of Sumio Goto's "Evening at Muro [Temple]," a remarkable work with the aspect of an ancient mandala painting. Or the haunting Chinese warriors on horseback in Yuji Tezuka's "Declining," or Sawato Fukui's simple old boat resting on the shore, with its ribs bleaching in the sun, and flowers curling at its base.

As the world shrinks, contemporary artists quickly flit across international boundaries, and one wonders if nihonga will retain its distinctly Japanese style. For example, several recent paintings are completely abstract, and apart from the materials, resemble oil paintings. Even so, they are not entirely self-conscious or totally obscure.

Personally, though, I feel nihonga is strongest at seeing the world in an actual grain of sand. It is fitting that the final painting is a portrait of a particular cherry tree in full flower, its ancient trunk dotted with tiny ferns.

As the Zen priest commented: "The most fluent is that which says nothing."