The Mark Morris Dance Group performs "Grand Duo." (Erin Baiano)

Philosophers and physicists can go on debating whether logic and unpredictability can coexist. Mark Morris has already answered the question.

Predictably enough, the Mark Morris Dance Group’s program at George Mason University over the weekend offered a cascade of surprises. Three of the works were new to local audiences, but the surprises bubbled up even in the welcome return of “Grand Duo,” with its propulsive, folk-dance score by Lou Harrison for violin and piano that is underpinned by meditative mystery but finishes with an exhilarating sensory rush.

As is typical for Morris, this program delivered a luxury of live music. “Pacific” was accompanied by excerpts from another magnificent Harrison work, “Trio for violin, cello and piano,” where the rumblings of a kind of sonic Siberian peat bog yielded gradually to a shower of light. Felix Mendelssohn’s tuneful “Songs Without Words” accompanied Morris’s frisky and enigmatic “Words.” Throughout the program, the excellent musicians were Colin Fowler on piano, Georgy Valtchev on violin and Robert Burkhart on cello.

A short, laugh-out-loud piece called “The ‘Tamil Film Songs in Stereo’ Pas de Deux,” which Morris created early in his career, in 1983, used taped music, a recording of what sounded like an Indian singing lesson.

But here’s the confounding part. Morris’s works unspool with airtight musical logic. His choreography follows the music in a rolling, running rhythm of phrasing and sudden punctuation, movements that fall somewhere between common activity and high stylization. It all feels utterly natural. Logical. How, then, to explain all the unpredictability?

“Words” performed by the Mark Morris Dance Group. (Ani Collier)

Take “Pacific,” which Morris created for the San Francisco Ballet in 1995 but which his company performed for the first time Saturday. The curtains open on three bare-chested men in long, flowing skirts; they throw their legs high, the skirt fabric falls in arcs, and they jump and turn in such synchrony with Harrison’s stormy music that you feel you’re watching the sound unwind from their bodies.

Sometimes the dancing tumbles with the turbulence of white water. Sometimes it’s small and delicate. In a duet section of “Pacific,” the woman pulls her partner up off the ground and in almost the same motion he swings her around in a little do-si-do. In a group, the women’s moves are weighted and heavy, the men are lighter, more mobile — an interesting contrast. They all coalesce in waves at the end, a unified uprising that threatens to spill over the stage.

You can see many choreographers who use music well, or well enough, whose dances respond to the beat, to rising and falling dynamics. But too often predictability wears through; you know what’s happening next. Repetition substitutes for development. That’s not the case with Morris. He introduces a motif, a raised hand, for instance, as in “Pacific.” He brings it back, but it feels changed; something about the musical timing or the lighting (in “Pacific,” it was by James F. Ingalls) or the accumulation of images around it makes it different. The raised hand has a new visual tone each time we see it, and finally, at the end, it’s part of that collective corporeal wall, everyone’s hands reaching up, and you feel like you’ve learned a new language.

The repeated movements arrive as surprises, because Morris is continually developing his visual field and the subtle emotions in it. His dances are all predetermined universes, a wonderful clockwork of certainty, yet with feeling: suspense, uncertainty. He keeps you guessing. “The ‘Tamil Film Songs’ ” pas de deux was a brief, hilarious story: A dance teacher gives his student all sorts of impossible combinations of steps, eventually driving her to a meltdown (something tells me this is autobiographical — Morris is no softie in the studio), but then assuaging her with a pretty costume and applause. But the whole thing rippled with inventiveness. No shoulders shimmied the same way twice, no foreleg flicked the same way again.

I wish Morris’s laws of nature could be more widely known. Other artists could learn from the way he computes his calculus of shape, position, timing, musical tempo. His work is an education in choreography, which is surely one of the most difficult of the arts — a reason why there is so little of it, and even less approaching Morris’s level of excellence.

But then again, maybe he should keep his secrets. They’re good for Morris, and for us. After his invigorating “Grand Duo,” you headed out into the cold with a party in your heart.