One of the unexpected by-products of this presidential campaign has been a renewed interest in the English language and a rediscovery in many quarters, no doubt, of a volume known as the dictionary.

We have Vice President Bush to thank for this fortuitous development since it was he who consulted the dictionary in a highly publicized effort to defend his use of the word "shame" during the debate.

In the same spirit of intellectual discovery, I consulted the dictionary to look up the word "nice," which has for years been used to characterize both President Reagan and Bush, and is often given as a reason by voters for the ticket's enormous popularity.

My research produced this definition: "having high standards of conduct, scrupulous, a generalized term of approval meaning variously, agreeable, pleasant, delightful, attractive, pretty, courteous and considerate, comforming to approved social standards, respectable, in good taste."

It is probably unrealistic to expect candidates to be "nice" during a political campaign, and it certainly would be boring as all get-out if they were. But it is not unrealistic to expect them to strike some balance between decent and vicious, lest they risk coming out of the campaign with their "nice" image in tatters. Bush is running that very danger.

His performance during the debate with Rep. Geraldine Ferraro, coupled with his postmortem remarks, raise a good many questions about what kind of person he is, and what kind of audience he is playing to.

A man who had established himself as having high standards of conduct came on during the debate like a cheerleader: he might as well have come out yelling "Give me an R!" At other times -- such as when he snarled at "those liberals in the House," -- he sounded like he had undergone a Richard Viguerie transplant. He spoke of an "evolution" in his position on abortion and one could only wonder which way his evolution would have gone if the winds on the Right had gone another way.

The signals he sent during the debate were the kind that speak volumes to any woman who has ever had to suffer condescending treatment from a man.

"Let me help you with the difference between Iran and Lebanon," he told Ferraro. She would have lost the debate on the spot had she not called him on it.

There was more. Asked what question he would like to ask Ferraro, he said he didn't have any: "I'd like to use the time to talk about the World Series."

The not-so-subliminal message: she has nothing worthwhile to say, let's talk about something important, like sports. It was insulting to Ferraro and insulting to the debate.

Ferraro has good reason to question whether remarks about her from the Bush camp were "planned." They have played on the standard negative stereotypes of women as being bitchy and ill-equipped to deal with such weighty issues as foreign policy. They have been, plain and simply, mean, whether they came in the form of malicious rhyming by his wife or outright insults ("too bitchy") from his press secretary. Bush topped them by introducing into the national politics what he claimed was an old Texas sports expression: "to kick a little ass." The expression, as anyone who has been around sports knows, is hardly confined to Texas.

It would, however, be better confined to sports.

Pollsters disagree on how important the character issue is in voters' decisions on candidates, but research published recently in the Handbook of Social Psychology found that emotions elicited by candidates -- fear, anger, hope, frustration -- along with character traits attributed to them, such as honesty, competence and integrity, were the top two influences on how people vote.

The Republican nomination in 1988 probably can't be won without the support of the evangelicals and the New Right. That political fact of life puts any reasonable politician in the position of having to search the dark recesses of his soul to find out what he is prepared to compromise, what he is willing to do in that quest. Bush is showing his answer.

He is betting his future on another old sports term: nice guys don't win ballgames. But this isn't a ballgame; it is a race to determine who will lead the country. Voters want to know what kind of people the candidates are, and how they behave during a campaign is the best indicator they have.

They don't need a dictionary to know the difference between a nice person and a mean one.