It was time for their quarterly checkup, the name that they gave to the coast-to-coast talks that had kept their friendship healthy over the past two years.

The two friends regularly went over their charts with each other. They checked off the condition of their vital organs - their kids and jobs, family and mutual friends - and probed their old wounds and fresh scars.

Inevitably, the woman on the East Coast came to the subject of her friend's father. She wanted to know how he was doing since the mother's death last fall. Well, the woman on the West Coast said hesitantly, her father was doing fine. He was, in fact, dating a nice woman, and it looked serious.

For a few moments you could hear the pennies clicking through the long distance line - pennies for one thought or another. They filled in the silence, as people often do when faced with an awkward medical bulletin, with all the right phrases: "As long as he's happy . . . It's good he isn't lonely . . ."

Finally, the woman on the West Coast, who is a poet, said: "It's not that I think it's wrong; it's just that I keep thinking: If it were my mother who was the survivor, she would just about now be getting ready to go to a movie with her sister." There was a pause and she sighed, "Women mourn, men replace."

The woman on the East Coast, who is a journalist, blurted out: "That's a gross generalization." The poet answered: "Yes, but a generalization is generally true."

The poet began to list the cases she had entered into the annals of this phenomenon. She had the names and addresses of three ex-husbands who, within the past six months, had gone from one home to another with a speed that would impress the van lines.

She knew a dozen men who dealt with women as if they were the essential but interchangeable batteries for their portable life-support systems. When one ran down, they went out and got another.

The women on the East Coast remembered the night last week when she, too, had had the same thought. She had been at dinner with a male friend who had just ended a five-year love affair. He had experienced, he told her fervently across the moo shi pork, the most horrible two weeks. Now, he would like her to meet his new love, Carolyn.

Women mourn, men replace. A gross generalization. Generally true.

The poet and the journalist wanted to figure out why. The poet suspected that men were more dependent on women. She knew many men who could keep only mold in their refrigerators - who were unable or simply unwilling to take care of themselves. She had an uncle who used to say - this was a family joke - that he'd remarried as soon as he'd run out of clean socks. The poet wondered how often women were just interchangeable need-fillers.

The journalist said stuffily: We are all, too degree or another, interchangeable. The poet said: Yes, it wasn't that fact that bothered her so much; it was the speed of the exchange. The women she knew went through staged withdrawals with all sorts of systoms, and had long resting periods before they felt ready to try again. But not the men.

Well, the journalist was by far the more flat-footed of the two. She took the argument and passed it over to the other hand for a moment. Wasn't it equally possible that "Women wallowed,men acted"? Maybe women believed too much in happiness. Maybe they romanticized themselves into massive depressions from which they refused to get up until they'd lost 10 pounds.

The poet disagreed. She thought that perhaps men tried to tough it out, while women tried to work it out. Men tended to close the doors behind them, to reject regret, to try and take a shortcut through grief. Women tended to, well, mourn.

To the joy of Ma Bell, the discussion went on and on. The journalist finally got impatient. There was too much in their talk that smacked of the old argument: Women Feel More.

Maybe it wasn't that at all. Maybe women would also take this shortcut if they could. Maybe they would replace, too, if only their fingers didn't freeze at the touch of a telephone dial. If only they were invited for a dinner party because the hostess needed an extra woman.

They both liked that argument.

They didn't believe it for a minute.

In the end, the two diagnosticians ran out of time, money and evidence. They were perhaps jealous of the apparent ease with which some men rebounded and recouped. They were suspicious of it, too. They had trouble deciding whether these men had a healthy reaction or a diseased one. But they knew one thing: They wouldn't want to catch it.

They believed in mourning as a way of paying respect to feelings. They were unable to believe that they could find a replacement part that would smooth a rupture. They believed that people had to heal themselves.

Well, this was the most expensive checkup they'd ever had. But, as the poet said, unpoetically, "It's cheaper than therapy."