IF YOU believe stainless steel is just as good as silver, you are too young to get married. Miss Manners urges you to put off having children until you either mature, or it becomes apparent that a congenital lack of sense should not be passed on to innocent children.

Young couples who think that silver is impractical should be told a few rough facts about what has happened to its price over the years before they attempt to discourage their relations and friends from giving them silver as wedding presents. Affordable presents are more likely now to be individual forks or spoons, rather than place settings, but there is still no opportunity like a wedding to get the basic pieces. In fact, it is the single most striking argument. Miss Manners knows against the "what difference does a piece of paper make" argument.

Miss Manners' idea of a basic place setting is slightly different from that of silver flatware manufacturers. Hers is the large knife, large fork, small fork and oval dessert spoon, with small knife as the choice if there is to be a fifth piece.

Teaspoons are properly used only for coffee and tea, and those confining themselves to the basics are not likely to use their silver at family breakfast or to give tea parties. The dessert spoon may be used for soup and cereal, as well as dessert. The small fork is used for salad, dessert (you run out and wash it during the cheese course) and luncheon, and may also fill in for the fish fork or the fruit fork before you acquire those luxuries. The small knife is also used for luncheon and for courses other than the meat couse, at which the large fork and knife are used.

After one has a service of place settings, then Miss Manners advises getting the teaspoon, the butter knife and the fish knife and fish fork.

Next in usefulness are the demitasse spoon (which certainly needn't match the table silver, as demitasse is served in the drawing room, but Miss Manners prefers those that do not say "Souvenir of Atlantic City"), the fruit knife and fork and, if you have leftover money and go in for that sort of thing, the oyster fork, the iced-teaspoon, the bouillon spoon, the grapefruit spoon or whatever else you can find.

In the time of great financial boom -- Miss Manners is thinking of the Industrial Revolution -- all kinds of strange implements where invented, and if you are rich and clever enough, you can set a table on which, as a lady of Miss Manners' acquaintance says of her inherited silver, it is not clear whether dinner is to be served or an operation performed.

Silver is marked with three initials of the bride's maiden name. This is particularly practical these days, when silver lasts a lady much longer than her average marriage.

A carving knife and fork, two large serving spoons, perhaps one of them slotted, another large fork and a small ladle are the basic serving implements, to which you can then add a soup ladle, a flat cake server that can also be used for quiches and such, asparagus tongues, grape scissors (nobody ever uses them, but Miss Manners adores them) large fish knife and fork, and so on. Why some people think they need special forks for serving cold meats, Miss Manners doesn't know, but then, not everyone understands why she needs asparagus servers.

As a secret tip, Miss Manners confides that sterling silver does not wear out. Therefore, buying it second hand, whether it is modern or antique, makes a great deal of sense. There is nothing quite so grand as setting a table with the kind of old European silver which is engraved on the back, thus giving your guests a terrible shock when, not knowing that those pieces are correctly placed with the fork prongs and spoon bowls facing the tablecloth, they concude that you have set the table upside down. MISS MANNERS RESPONDS

Q: I often have the chance to give bridal and baby showers, and love doing so. A problem often arises with the invitations. My mother says that I should sent them to friends and relatives who live out of town or state, just to be courteous. I feel that a shower is only for those who live near and that the others will give their gift at the wedding or send a congratulatory note with a possible gift. Postage is so high, and invitations aren't cheap, either. What do you say?

A. Miss Manners hates to go against the judgment of mothers pleading for courtesy, but she has to say that you are correct. Perhaps your mother is confusing the courtesy of inviting people to weddings without presuming to anticipate whether they will be able to attend. One does not do that with lesser parties. A wedding is considered to be enough of an event to make a trip worthwhile, but a shower, however pleasant is not.