To the best of my knowledge, no major league baseball owners and only two players are under the age of 21. We must assume that the current dispute between these two groups involves grown men.

Presumably they are all old enough to know that nobody wins a war. Once the fighting begins, there are only losers. The contest is fought not to determine which side will win but which side will lose the most.

If grown men know that everybody in a war loses, we must wonder why they permitted their disagreement to escalate into economic warfare.

Two possibilities come to mind:

Each side thinks it has enough clout to inflict more damage on the other side than it will itself sustain.

Both sides think that the issues involved are worth fighting over, even as men are willing to fight and die for principle in a real war.

The first answer can be dismissed because if both sides think they can "win," at least one side must be wrong.

The second proposition may have validity when one is defending his homeland, his family, or concepts like freedom and human rights. Civilized people should not have to fight and die to settle a labor contract.

En route to senility, we learn a few things. One of the things I have learned is: Be slow to judge an issue over which others are willing to fight.

I am especially slow to form opinions about labor disputes because they usually involve a "package" of many complicated issues.

So I make no judgment about the rights and wrongs in baseball's labor dispute. In fact, it is easy to remain dispassionate about a disagreement between millionaire players and millionaire owners, just as it is when Johnny Carson tangles with NBC.

But I do have some opinions about strategy and tactics. It appears to me that if the owners hold out for two weeks, the players will lose badly.

After two weeks, strike insurance will give the owners millions of dollars worth of protection. Even Calvin Griffith and his kinfolk, whose incomes depend almost entirely on baseball, will be able to survive. And most team owners are richer than the Griffiths.

On the other hand, players deprived of their paychecks for the remainder of the season will have time to wonder in what other line of work they can earn comparable salaries. Their enthusiasm for economic warfare may begin to leak badly by Dec. 31.

So the best strategy for the players would appear to be to get back to the bargaining table as quickly as possible and try to win whatever concessions can be won in a few days. If the players are smart, they won't give the owners a chance to start collecting on their insurance policy.

Now that a strike has been called, persuasion will to a large extent be replaced by the application of economic power. Each side must now ask itself, "Is it time to cut my losses and admit defeat? What, if anything, will I gain by continuing a fight I am foredoomed to lose?"

Both sides must keep in mind that a prolonged shutdown will hurt both sides. Baseball may have been "the only game in town" in 1900, but in 1981 it is not. There are too many other entertainments and diversions available to the public.

After television stations schedule new programs into time slots now occupied by baseball, and after fans find new ways to spend their time and money, it will be difficult for baseball to reestablish itself.

It is unwise to give customers an opportunity to discover that they can survive quite comfortably without you.

If "the boys of summer" are really grown men, they won't do it.