The ground started slipping away on Wednesday when for the first time a reporter comprehended dimly what a scientist was talking about.

Up until then the Einstein Centennial Symposium, which began the first of the week at the Institute for Advanced Study here, consisted of papers bristling with formulae of no known application, and one therefore could feel very comfortable.

You were secure, indeed, seeing perhaps 19 Nobel laureates on all sides of your chair in the lecture hall. Outside the great glass windows many white birches sprang from green grass. We're bound to be all right, Jack, with men of such brilliance keeping tabs on the galaxies and holes. There are black holes and white holes, and God only knows what others remain to fill out the spectrum.

Nothing too unusual could be happening, one was sure, since there was the clebrated P.A.M. Dirac, now very old, at one's table at lunch. He was not drinking wine and was hunting about for a dessert because, as a learned man said, the taste for sweet increases with age.

But how unfair, to want sweets at the very time of life the risk of diabetes increases.

"Well," said a man far gone in scientific learning, "It makes mortality great."

The instutute's director, Dr. Harry Woolf, told a reporter not to feel bad if he understood nothing of the various papers that were read.

"Most of us do not understand many things in these papers. But a few do.

"One great purpose of the institute is to nourish a pool of talent sufficiently abundant that when the great genius appears he will be recognized."

Then he added: "I once had a teacher, not a very good one perhaps, who lost patience with some students. He said, 'How can I teach you anything? You don't know anything.'"

Even if one did not know enough to learn at the seminar it was good to think humanity is far advanced in formulas with factors of 57, and numerous lambdas, gammas and other Greek letters. Surely our universe is known infinitely well by now? And even if an individual is ignorant surely he could enjoy vicariously the advance of science in all directions.

And then came Wednesday and a somewhat suspicious sounding paper on "The Size and Shape of the Universe."

The title suggested we may not know as much about the shapr and size as one had supposed. The speaker. Martin J. Rees of Cambridge University, spoke quickly, articulately and brilliantly, buy those without substantial scientific background knew no more than on Tuesday.

"I understood him to say the universe was roughly the shape of a golf ball," said a learned man in a discussion afterwards.

"Oh, I heard nothing of golf balls," said a science attache from the Swiss embassy. "I gathered an expansion right into infinity."

If one missed both the golf ball and the expansion, one was at least left with some doubt about the shape and size of both.

But the worst jolts came yesterday afternoon as John Archibald Wheeler spoke on "Beyond the Black Hole."

Now a black hole, as everyone knows by now, is an area of the sky in which a star has collapsed. Its matter has condensed more and more until there is nothing left to speak of except a gravity field of incredible strength. Somewhat like the cheshire cat that grew smaller and smaller until nothing was left but the grin.

If anything -- any particle -- falls into a black hole it vanishes forever and we can never know what becane of it because not even a wave of light can escape from that gravity.

Dante once spoke of the love that governs the fixed stars.

One might wonder what happened to the love that governs the stars. Here a poor star has shrunk to nothing, leaving behind no sweet memory of life but a demonic force to destroy anything coming too close.

When Wheeler spoke of "beyond" the black hole he had nothing cheerful to say about getting out of it. Instead, he questioned the "laws of physics" themselves, at least as ordinary people know them.

To make it simple, he gave an example from a time in which he was playing the parlor game of 20 Questions.

"Is it vegetable?" he first asked.

"Mineral?" and the answer was yes. So he went on using up his questions. He thought it strange that those who gave the answers took so long to say a simple yes or no. But at last, from the answers to his questions, he decided the correct answer was the word "cloud."

"Yes," he was told -- the word was indeed cloud and he had gotten it right.

But then it turned out there had been no answer, no right solution, at the beginning of the game. Those playing with him had decided not to have an answer, but would let him ask his questions all the same.

Both the questioner and those with whom he was playing reached the answer together. It was correct and sensible, but if he had asked other questions and gotten answers along the way he would have reached a totally different word and it too would have been correct.

Before he asked the questions there was no correct answer. Afterwards there was an answer and it was correct.

There are no laws of physics until humans ask what the laws are, he speculated, and then what the correct answer is depends in part on what questions are asked.

It was said that Einstein himself thought the laws of the universe were transcendent, quite independent of any questions asked or not asked.

But here was one of the most respected minds in America suggesting that the questioner has much to do with what the laws really are.

This may suggest what is meant when people say science in her far reaches and frontiers is concerned less with the weight of a certain particle than with such questions as why a universe exists in the first place and whether it could be remade after a Big Crunch or universal wearing out. The questions approach the fields of philosophy and metaphysics.

Wheeler showed an unexpected modesty, too, saying the more science learns the more it sees how much there is to know.

The poet Cummings once spoke of "always the beautiful answer that asks the more beautiful question."

Poets have long argued an endless progression in consciousness, and mathematicians have recently concluded that mathematics are infinite. Maybe it will be found true that the laws of physics are also infinite, and can never be pinned down once and for all, but always lead to higher questions and higher syntheses.

It's not quite the same thing we grew up thinking.

And yet if there was a sense of the ground slipping away there was firm ground of another kind.

English theoretician Stephen Hawking was seen at every session in his wheelchair. He has sometimes been called the equal of Einstein in brilliance. He attended because Einstein was always one of his heroes.

But he left his studies at Cambridge University in a wheelchair because amytrophic lateral schlerosis has wasted his muscles and nervous system though leaving the ability to think intact.

Only by huge effort can he raise his head, and his speech can only be understood by his intimates who relay it to others. He is still in his 30s.

Both his brilliance and his plight command respect here and possibly something more. He smiles a great deal and seems to be very happy.

What if the gorgeousness of physics is less in the splendor of natural law and more in the vulnerable living physicist?