"Your President Carter is the greatest gamble of this century and not just for your own country but for the rest of the world."

These words were spoken by a Britisher, a long-time friend, who is now in the House of Lords. They contain, it seems to me, a fundamental truth about the status of Jimmy Carter both at home and abroad. He has a reservior of good will and hope for his success, together with a realization that if he fails there is no predicting in what direction the West will move.

In the first six months a great deal of critism has been withheld. Even among those who might be partisan political opponents, the inclination has been to give him a chance: Don't try to pull him down before he has time to show that he can cope with the horrendous problems confronting the President after the Watergate and the recession.

Today, however, the hopeful interlude is ending. It is being said increasingly that the Carter foreign policy is going nowhere or, rather , it is going on several different directions at once. While Carter profess to be unable to understand why the human-rights pressure should cut across the attempts to reach a new strategic arms limitation agreement, that is surely no mystery to anyone with even a slight understanding of a totalitarian system.

In Europe recently the frequent private appraisal was: Yes, human rights is a laudable demand; but as far as the Soviet Union is concerned, the end result can only be negative. The controls are so tight, together with incessant propoganda, that even an intimation of change must be restricted by every possible means no matter how ruthless and brutal they appear to the world beyond the Iron Curtain.

The critics most often mentioned the letter the President wrote to dissident physicist Andrei Sakharov, which was delivered by the American embassy in Moscow. That, they felt, went beyond the bounds of moral suasion and impinged on Soviet sovereignty. They linked this with the President's reception of Vladimir Bukovsky, the dissident expelled from the Soviet Union.

Along with the human-rights issue, the propoganda of the weapons lobby and the uncertain course of Congress in advancing the neutron bomb have deflated the hope of meeting the October deadline for a new arom-control agreement. How much of this is the fault of U.S. negotiating proposals that blow alternately hot and cold only history - and a full disclosure of secret documents - will tell. But with the average offered by tha stalemate and the pressures of the weaponeers a new and accelerated round of the arms race seems almost inevitable.

As for the precarious balance in the Middle East, Carter and, indirectly, his national security adviser, Zbigniew Brzezinski, have talked too much on one side and the other. At his last press conference the President foreswore any more talk, at least until he has a chance to meet with the new Israeli prime minister, Menachem Begin - a ban he quickly violated.

The President has sent a whole series of proposals of domestic policy to Congress. More often than not they have had the air of intellectual concepts rather than political proposals that meet the desires and the understanding of the average citizen.

In his energy bill, Carter tried to do too much. The need for a straight forward proposal that would conserve energy even at the cost of much higher gasoline prices or even, as he now has suggested, gasoline rationing. Instead, it had the look of a Rube Goldberg contraption that would modify the tax laws, control and/or decontrol oil and natural gas, and convert unwilling Americans into voluntary conservers. Congress is meddling with it and the likelihood is a measure that will please no one.

One thing I wish Carter would stop doing is dredging up his campaign promises, apparently in the hope that he can be proved an honest man. He keeps repeating that he will balance the budget by 1980 or 1981. With the prospective deficit running at close to $60 billion, that would seem an exercise comparable to squaring the circle.

But, you see, he and the man around him are learning. This is often said in the six-month trial run. Is there time for on-the-job learning? I go on hoping he will succeed. As my friend in London puts it, so very much turns on the outcome.