Casually bestowed friendliness is such a marvelous American trait, a manifestation of the freedom, generosity and human kindliness of a democratic people. Who could ever say a word against friendliness?

Miss Manners can at least try. What's the fun of living in a free country if you can't rile everyone all up with an unpopular argument now and again?

Therefore, while she cannot bring herself to come out in favor of unfriendliness, she submits to you the thesis that friendliness is not always appropriate and can often be offensive.

Consider, for example, the attempted friendliness of strange men on subways to unprotected young women. Or the innocent friendliness of people who are chatty on an airplane when one is trying to work or sleep.

But even these, such as they are, represent social overtures of one kind or another. The friendliness that Miss Manners wishes to attack today is well-meant friendliness, designed to make strangers feel that they are among friends. When this is done in situations where friendliness is inappropriate, strangers can feel worse if they are required to act as if every occasion were social.

How's that? Perhaps you think that people are always more comfortable in an atmosphere of friendship. Let us consider some particular cases.

1. You are having a physical examination or treatment in a doctor's office or a hospital. The medical staff people, some of whom you never saw before in your life and perhaps some of them half your age, address you by your first name.

You could suspect that the doctors do this out of condescension, expecting you to address them by title and surname, but nurses and orderlies may be wearing first-name-only tags themselves and be quite prepared for you to reciprocate. You know they, at least, are only trying to be friendly, but you feel uncomfortable without knowing why.

Miss Manners will tell you why. It is because if you were among friends, you wouldn't be exposed while they were dressed. Which you would all be, Miss Manners does not presume to say. But the convention of the impersonal situation, which makes it respectable for others to see you unclothed, has been violated, leaving you feeling -- well, naked.

2. You are a woman (Miss Manners could make this situation unisex, but it is not worth the trouble) who has ordered breakfast served in your hotel room, and have put on a robe to receive the table and sign the bill. The waiter admires your looks, or perhaps just asks you where you are from, or how long you plan to be in town. Although you do not suspect him of criminal intentions, you feel frightened.

Again, a tacit agreement has been destroyed. By the customs of hotelkeeping, a woman may wear night clothes in her room because room service and cleaning people observe the convention of being rigidly unobservant.

A friendly remark shatters this delusion, and leaves the woman realizing that she is in a hotel room with a strange man, wearing her negligee.

3. You are on the telephone, and a stranger addresses you familiarly and makes personal inquiries. Perhaps it is someone who has called you, and, misled into believing that this is someone you know so well that you are expected to recognize the voice, you reply in a friendly fashion. Then you find that it is someone who wants to sell you something, or to extract some favor you do not care to grant. Feeling like a fool puts you at a great disadvantage.

Or perhaps you placed the call, and an intermediary -- an operator, or the secretary or a family member of the person you are calling -- takes the call in a friendly way, again by addressing you in terms or with inquiries appropriate only to friendship. You are left uncertain as to how this person will represent you to the one you are calling, or whether there is a reason for the seemingly aimless questions. In any case, you have spent time in socializing with someone you don't know.

4. A colleague, employe or your boss takes you into his or her confidence, repeatedly informing you of personal troubles ranging from emotional crises to transportation breakdowns. Your sympathies for a fellow human being are aroused, and you try to disassociate your compassion from an increasing irritation that you are also asked by this person to work extra, lend money, overlook late checks or otherwise compensate for those troubles.

Yet, they are related. The work contract carries the assumption that everyone can manage to perform his obligations except in rare emergencies. But friendship means making allowances for the failings and troubles of friends, without counting whether the favors are strictly reciprocal. By enlisting your friendly interest in his or her troubles, a business associate confers on you the social obligation of tolerance.

And in all of these cases, you have been deprived of the right to choose your friends before assuming the duties of friendship.

Q: It seems that few people know the meaning behind giving roses. Will you explain the meanings behind the different colors of roses (white, red, yellow, etc.), and the difference in giving a single rose, as opposed to a dozen.

A: A single rose is cheaper than a dozen, although not always 12 times as cheap. However, that is an extremely rude thing for the recipient of roses to notice.

There are as many versions of the symbolism of flowers as there are of which wedding anniversary is associated with sapphires or with software. Kate Greenaway's "Language of Flowers" has, for example, a list of "meanings" for roses of different colors and stages of development, ranging from "Tranquilize my anxiety" to "Beauty is your only attraction."

A withered white rose, it states, means "Transient impressions," while an unwithered one means "I am worthy of you" and a white rosebud means "Girlhood." But if a yellow rose means, as is claimed, "Decrease of love; jealousy," who would send any? In neither of these states of a romance does one generally think of sending roses.

You may count only on most people's understanding that red roses have to do with romantic love, and everyone's understanding that sending any roses at all has to do with "Thinking of you" if not also "Hang the expense."

Q: My husband and I are confused about tipping individuals with whom we have negotiated a price for a service. We travel, and understand hotel and restaurant tips, but when we take a bus tour or a private helicopter flight, do we tip the driver or pilot? In our home, do we tip the man who trims the trees, the men who put on the roof or their bosses, or the woman who measured our drapes?

A: Tipping has long ceased to be a matter of expressing a financial opinion of services rendered. All it means now is that part of the expected wages, for certain jobs, are paid only at the discretion of the client.

It is all very well to imagine that clients exercise this privilege by rewarding hard workers and penalizing poor ones. In practice, it is all too common for "maitre d's" to be given huge fees for doing nothing haughtily, and harried waitresses given next to nothing.

At any rate, the jobs you mention are not those with which tipping is associated. Tipping, when it is unexpected, is sometimes taken as an insult -- although extra money, in a business situation, never is. All you have to do, if you want to show special appreciation of a job well done, is to call it a bonus.

Q: I would like to have engraved calling cards made, mainly for enclosing in gifts, and should like to know the correct way to use them to indicate the gift is from both my husband and myself. May I have the cards engraved to read "Mr. and Mrs. William Thusandso" or should I have them "Mrs. William Thusandso" and pen in "Mr. and" before my name? Perhaps neither is acceptable.

A: Why are you so pessimistic? Both are correct, but actually, you are in even greater luck than that. So is Miss Manners, who rarely has the opportunity to tell people how to be faultlessly correct and to save money at the same time. You are about to receive such valuable advice.

Have your cards engraved "Mr. and Mrs. William Thusandso." (Are you by any chance related to the Philadelphia Thusandsos? Miss Manners went to school with one of the girls and hopes things turned out all right for her, after all.) Should you need cards of your own, for sending separate presents or making morning calls, you need only ask the engraver to wax out the words "Mr. and" on the engraving plate, run off cards that will then read "Mrs. William Thusandso," and then remove the wax for the next time you want joint cards made.