The Senate Finance Committee is talking cents this week. Eight cents. Sixteen cents. Thirty-two cents. With any luck, it may even be talking common sense.

The subject on the table -- no ashtrays, please -- is smoking and taxes. The question is whether Congress will lower, raise or maintain the excise tax on cigarettes.

At the moment, the tax rate is 16 cents per pack. This is relatively less than in 1951. But if Congress does nothing, on Oct. 1 the figure will be halved, with 8 cents chopped off the consumer price tag.

In the larger scheme of things, 8 cents doesn't mean a heck of a lot. But -- this is beginning to sound like a line from "Pajama Game" -- give it to the government on every pack, 30 billion packs a year and it adds up to nearl $2.5 billion.

As you might imagine, it is an odd moment in deficit financing to go looking for ways to take several billion out of the federal treasury. This is a tax that is actually popular. In a Yankelovich poll, more than three-quarters of the American public chose cigarette taxes as their favorite way to raise money for the deficit. That included smokers.

It is an even more peculiar moment for the government to be actively promoting such a deadly habit. A study by the Office of Technology Assessment estimates that Americans spend $35 billion a year on diseases caused by smoking. Smoking is lethal. Why push it with a discount?

In fairness, cigarette consumption among adults doesn't rise or fall with the price tag. Few adults stop smoking just because the cost has gone up. Even when adult smokers know the real price the cigarettes are exacting on their lungs, smoking is a brutal addiction to conquer.

But there is solid evidence that cost has an effect on the youngest consumers who arenhooked. The typical American who leaves high school as a confirmed smoker picks up the habit in junior high, when money is tightest. The older you get, the less likely you are to start smoking.

If we were to cut the cigarette tax and the price per pack went down, a million young people between the ages of 12 and 25 would begin, or continue, smoking, according to an estimate by The Institute for the Study of Smoking Behavior and Policy at Harvard.

When you figure the long-term health effects of this tax policy, Kenneth Warner of the University of Michigan's school of public health says bluntly, "If that tax is allowed to fall in half, upwards of half-a-million Americans will die earlier than if the tax had been left at 16 cents."

The House Ways and Means Committee has already voted to keep the 16-cent tax. Things are less certain in the Senate, especially since Majority Leader Bob Dole is in favor of a return to the 8-cent tax. But the most attractive of the Senate bills under consideration would go in the anti-Dole, anti-Helms, anti-tobacco lobby direction. It would raise the tax to 32 cents.

One such bill would earmark part of the new money for health education and part for Medicare. This is an attractive notion, since some $5 billion in Medicare-Medicaid bills annually can be attributed to smoking. Cigarette smokers would prepay a piece of their future health costs with each drag.

But again, the greatest appeal is not in terms of raising revenue but in discouraging smoking. The same studies show that any 16-cent increase would likely diminish the number of teen-age smokers by 17 percent, or 820,000.

"In general," says Kenneth Warner, "I don't like the idea of using tax policy to influence behavior. But consider the behavior. We're dealing with a highly addictive process. Ninety percent of adults says they'd like to quit if it were easy to do so; 60 percent claim they have tried within the past year."

He sees a subtle "educational" value in a major tax raise. "I'm an economist. We talk about market failure. People do not understand the results of the market behavior called smokTAKE 248355 PAGE 00003 TIME 12:24 DATE 09-17-85 ing. By raising the dollar price, we're providing information. We're saying, 'This is costly.' That's not just in dollars; that's in terms of health implications too."

It seems unlikely that we'll get our 32 cents' habit some senators have acquired of caving in to the tobacco lobby is addictive. But at the very least, they should maintain the current 16 cents. It's one tax that's certifiably good for our health.