Gasoline prices going down and natural gas prices going up. What is the American consumer supposed to think - and do? First, remember that the situation could change as it has in the past.
Second, maintain the prudent thrust toward efficient use of energy that is saving money now and that can prolong long-term supply of these valuable resources.
A return to energy profligacy under OPEC oil price cuts would riddle world oil production that is now projected to peak in 1990 and decline thereafter. It would also put an unnecessary drain on natural gas, whose US production is expected to rise only until 1985 even under a high-side scenario, though total world production will keep rising to the end of the century.
Fortunately, some measures for conservation and efficiency have become sufficiently established to have a continuing effect on energy use. People are not going to pull the new insulation out of their houses just because heating oil prices drop. Even ''big'' cars, which might tempt buyers as gasoline prices fall, are now built to use less fuel than equivalent gas guzzlers of the past. More and more results are expected to be felt as business and industry put into full operation the energy-efficient equipment to which they have been switching since the oil crisis a decade ago.
The imponderable is what happens to individual and institutional conservation habits as lower-cost energy looms along with economic recovery calling for more energy use. We recall hundreds of letters from readers sharing their experience, satisfaction, and even delight in using energy more efficiently. It seems unlikely that all the pleasures of new-fashioned thrift will be abandoned; their rewards in a sense of public-spirited accomplishment will remain even if the out-of-pocket savings are less.
Indeed, for natural gas users, it appears that even the cash value of conservation will continue to climb along with prices. Why these prices have risen so much under the present phased decontrol legislation ought to be thoroughly aired in congressional hearings on President Reagan's proposal for accelerated decontrol.
Perhaps the most important thing to come out of these hearings would be assurance to the public that whatever steps are taken will be in the public interest. The administration currently carries the burden of an investigation raising questions about favoring industry over the public good in the Environmental Protection Agency. It faces congressional and consumer critics convinced its new gas legislation would also favor industry over the public good.
Deregulation lobbyists will be on their mettle to present their case without the suspicion of taint that helped prevent deregulating the price of gas long ago. Back in 1956 both houses of Congress voted for deregulation, but a senator who voted against it complained that a lobbyist had left him an envelope with 25 Eisenhower vetoed the bill even though he favored deregulation. He blamed an ''arrogant'' natural gas lobby and said he could not risk doubt among the American public about the integrity of governmental processes. This integrity is under particular scrutiny today as the proliferation of political action committees has focused attention on the political influence of money.
The arguments about speeded gas deregu-lation should be on the merits. There are plenty of these to be discussed. They include the difficult and conflicting claims over the costs to residential and industry users (at least one state gas distributor has already gotten permission to cutm its gas rates to industrial users to compete with oil); the question of incentives for gas exploration (under present partial deregulation more exploratory wells were sunk for gas in 1981 than for oil under full deregulation); the effect of the network of pipelines and state and local regulations that could keep market forces from fully operating on natural gas even under federal deregulation.
Here is certainly an issue to which should be applied the test that budget director David Stockman originally advocated for all government programs. Each should be accepted or rejected on the strength of its own merits, not on the strength of the interests supporting it.
An American public satisfied of a law's integrity on this basis should be all the more ready to do its part for the country's energy future.