A little yin, a little yang, a touch of philosophy and a smattering of physics make up the golf game of Tom Sieckmann, who comes here by way of Singapore, Bangkok and Perth.

That strange mixture produced a score of 67 in the Kemper Open yesterday, tying him for second place. Right there behind Fred Couples and his 64, and even with Larry Mize and Charlie Bolling at 5 under par, is this rawboned no-name player with a benevolent and worldly expression.

Sieckmann produced six birdies and one eagle to leap onto Congressional's leader board, a considerable accomplishment for a 31-year-old who earned his PGA Tour card in 1984 after a golf education in the exurbs of the world. Never mind that the last thing he won was the Philippine Open in 1981. This guy reads everything, sometimes for four or five hours at a stretch. His favorite book is "The Dancing Wu-Li Masters," and he can putt.

"I'm the kind who needs to know how things work and why things happen," he said.

He has a penchant for out-of-the-way places, foreign philosophies and Newton's laws. He caught malaria in India, he caught a lot of things from bad water in other places, and he has been stranded on several continents without a dime. He speaks Spanish, knows some Portuguese, and can even throw in a couple of words in Tagalog, the native language of the Philippines, although that nation mainly speaks English, as Sieckmann will patiently explain.

Along the way he learned how to play some decent golf, although it is just beginning to show, with his U.S. tour career earnings of $73,517 barely enough for plane fare to Brazil, another place he has been. But he finished first in the 1985 qualifying school and, after learning the ways of the tour last year, he has produced some promising play in 1986. He finished third in New Orleans and in the money in nine of 16 tournaments to earn $43,465, enough to survive on.

How Sieckmann got to all those places and back to the PGA Tour is an improbable story, for he is a distinctly American, strapping, 6-foot-5 product of Omaha, with a shock of blond hair and a droopy handlebar mustache. He came late to golf courses, first dabbling in football and basketball, for which he seemed better made at 205 pounds. He spent a year at the University of Nebraska, playing junior varsity basketball, then transferred to Oklahoma State. He took business courses but did not get a degree, preferring to "major in golf."

It turned out to be a natural sport for him, at least from a thinking man's standpoint; team sports lost their charm when compared to the deep intricacies of a golf course. First, however, he had to gain some experience, so he went abroad. From 1977 to 1984 he played in Europe, the Orient, Australia, Latin America, anywhere that had a golf course. His breakthrough came in 1981, when he won six foreign events, including the Philippine, Thailand, Singapore and Brazil opens.

In the meantime, he picked up some valuable lessons, playing with the best of the foreign competition. Among those he encountered were Spain's Seve Ballesteros, Australia's Greg Norman, Scotland's Sandy Lyle and West Germany's Bernhard Langer.

"The competition wasn't as tough as here, but the courses were good and there were some players to learn from," he said. "I was playing with them when no one had even heard of them. I'd come back and say, 'Hey, there's some good players over there.' "

Because of his late start, Sieckmann is still shaping his game. He has become a perennial student of the mechanics of golf who tinkers incessantly with his swing and watches videotape for hours. Golf courses are not so much playing fields for him as they are problem sets, but Sieckmann may be almost too analytical for his own good.

"It probably hurts me a little," he said. "Golf is a game that you're better off not thinking about too much. Just aim it and hit it. But I'm that kind who likes to find out how things work . . . I like the challenge of you against the course. It's not nearly as much fun to beat someone else as it is the course."

It seemed somewhat unfair that on a day when he produced some of his best play, Sieckmann was confronted with Couples' record-tying score.

Sieckmann birdied the par-3 second hole with a 20-foot putt and the par-4 fourth with a 5-iron to 10 feet. He birdied the fifth, sixth and seventh holes with putts of eight, 15 and five feet, respectively.

He bogeyed the ninth hole from a bunker, then eagled the 10th, reaching the par-5 green with a 5-iron downwind and sinking a 30-foot putt. His final birdie came on the 17th with a 15-footer, making up for bogeys on the 12th and 13th.

But after knocking around the Orient, and having spent considerable time in golf capitals such as Akron, Ohio, as well, Sieckmann has learned more about the game than the tempo of his swing.

"You have to get used to that happening out here," he said of Couples' performance. "It's not like any other sport. If he birdies every hole, there's not a lot you can do about it except try to birdie every hole, too."