Somebody out there must have been listening to our grandparents. You know the line: "If you have your health, you have everything."

In any case, the Quaker Oats people have come up with a boffo idea for the people who have everything. They have decided to reward them with even more. They are going to give bonuses to workers who have had the wisdom and foresight not to get sick.

Say, for example, you are a Quaker Oats worker and manage to avoid any illness worse than a cold for the entire year and never used your medical benefits. You could be rewarded with as much as $300. If you keep medical bills below the target, you can still get a dividend worth $100 or so.

What is so delicious about this plan is that, once again, the private sector has come up with innovations that would be just nifty for the public sector. It has designed the perfect national health plan for the economically strapped '80s, a plan more Reaganistic than the White House economists could have devised.

Until now, while health costs have been rising at three times the rate of the consumer price index, the government has only offered a stick or, rather, a scissors. The new budget, for example, merely cuts health benefits for the aged and infirm. But under the new national health plan, the government could offer a Quaker Oats carrot.

Instead of just tantalizing people who get sick, they could give them an economic incentive to stay away from disease: bonuses for the poor who don't use their Medicare or Medicaid at all.

At first glance, it might seem a bit peculiar to offer people money for staying healthy. But surely only a tattered group of knee-jerk liberals would object. The rest of us have learned our lesson. What did we get for helping sick people? Sick people.

But this is the '80s, and we no longer reward the needy. We reward the people who don't need us. Consider, for example, the current economic program. We don't like to put benefits in the pockets of the poor anymore. This merely encourages them.

Today, we prefer to give money to the people who are rich, as a sort of national incentive plan. The idea that being rich is better than being poor is supposed to slowly trickle down, even to the befuddled underclasses.

What we are talking about is mind over matter, an economy over a society. So it only makes sense to distribute sick benefits to the healthy.

I grant you that the Quaker Oats people were probably just trying to eliminate unnecessary trips to the doctor, the fender-benders of the health business. But since the national public health coffer is in such dire straits, the federal government needs a more radical plan.

The big spenders, those who come down with catastrophic illness, will have to be dealt with in a more creative way than by simply cutting funds as Reagan has done in the budget. To keep the healthy as wealthy and wise as before, we need a preventive medicine bonus to encourage good citizens not to develop cancer or heart disease.

We might also suggest a moderate stipend to those who do not need a liver transplant or a kidney dialysis, and perhaps an additional incentive for people who do not allow their children to have handicaps.

The beauty of this program is that it fits into the administration's penchant for rewarding people for not using things. At the moment, for example, it has one plan to ply some farmers with produce if they don't plant their land. It has another to award parents with vouchers or tax credits if they don't send their children to public schools. Surely we could credit people for not filling a hospital bed.

In the current ideal of independence, the good private citizens of the 1980s are the ones who make no demands on public services. They educate, employ, and transport themselves. The motto of this new national health plan would be a perfect match: Citizen, Heal Thyself.

Lest you think this is just a fantasy, imagine the public relations bonanza. The president ventures out of the White House again to deliver the first bonus checks. There, arm around the healthiest specimen, he tries once again to convince us that, yes, he is "getting America on the mend again."