Distinguishing between counting and not counting, between "time in" and "time out," is probably the single most basic skill a game player, fan, or official must possess. Without it, a participant or observer could not tell the difference between the preliminaries (such as a warm-up), the breaks in the action (such as a time-out), the aftermath (such as a handshake or a victory lap) and the game itself, could not know when to expend energy and when to relax, could not keep score accurately, could not determine what behavior was affecting the outcome, and so on.

Obviously, we learn to make these distinctions, but we learn them without being aware, for the most part, that we are learning anything. As a result, the process by which we decide that a game is being played is generally hidden from us and therefore seems perfectly natural, not something that has to be learned.

We forget that children, people from other cultures, and adults in our own culture who are unfamiliar with the game cannot automatically tell which actions are part of the game and which are not.

But even if someone understands the notions of play (#1 in our list above), recognizes when a particular game/sport is being played (#2) and is familiar with its object and "official" (written) rules (#3 and #4), such a person would have difficulty participating in the game/sport at any level without a great deal of additional information (or "rules") about the activity.


The outsider

To illustrate this notion, let us imagine a person named Leslie who has taken extensive tennis lessons, memorized an official USTA rule book, and watched professional tennis on television but never actually played a match at any level and never played or watched or read about any other games (which presumably share some of the unstated rules of tennis).

One day, let's suppose further, someone invites Leslie to substitute in one of our doubles games. Even assuming his skills were similar to ours, I would venture to say that Leslie would not have much fun and would make the rest of us very unhappy. He would almost certainly get very confused and frustrated at the way my friends and I play "tennis."

In fact, Leslie might not even recognize it as tennis at all and might conclude that we are playing some bastardized form of the game.

And in a sense he would be absolutely right.


By the book

For one thing, as Leslie would be dismayed to discover, none of our rules are "official," in the sense that they are written down or formally agreed upon.

We all seem to assume that we are following the most important rules of professional tennis, except where that is not possible. So, for example, when the ATP adopted a tiebreaker rule for deciding a set, most (but not all) of the games I was involved with also adopted that practice.

In general, the only rules we discuss are those we are uncertain about, such as whether it is legal to touch the net during a point or hit the ball before it crosses the net. Otherwise, we have never spelled out the "rules" we are using, have never stated which set of "official" laws we will abide by, have never established an authority to settle disputes, and have never ever consulted a rule book (at least not at the court) to determine the "correct" way to play. When we disagree about the rules, which rarely happens, we use our knowledge of pro tennis to defend our position.


Not by the book

But we certainly don't do everything as they do on the ATP tour. As I have already indicated, we give people a second chance at a first serve according to our own lights, not what we see happening at Wimbledon.

To save money, we do not open a new can of balls every seven games, and when we play indoors (where we have to pay for court time), we switch ends of the court after each set, not after every odd game.

In addition, we never assess penalty points for swearing, racquet abuse, exceeding time limits, or footfaulting. We might grumble about these violations, especially if we think a player is getting an unfair advantage, but we tolerate them, apparently because we perceive them as too trivial to worry about.

Yet some of the people I play with are fanatical about the height of the net. They use a tape measure to make sure the middle of the net is exactly 36 inches high and raise or lower it as needed. They even bring "doubles sticks" to raise the net to the appropriate height at the sides. Wouldn't our "inconsistency" drive Leslie crazy?

Obviously, one of the most crucial (and rarely stated) meta-rules of games that someone like Leslie (or a computer or a dolphin) would not understand is that we can play them any way we wish, as long as we have (apparent) agreement among the participants. If we want to play tennis with a racquetball or without a net, what's to stop us?


Tradition-bound

And yet, in my experience, few people choose to play games or sports in innovative ways. Although they are willing to eliminate "trivial" or inessential rules, most people evidently want to feel connected to the tradition of "real" games (i.e., professional sports), even when the rules of the pro version are inappropriate for the local circumstances.

So, for instance, almost all junior high school basketball hoops are 10 feet high, just as they are for the Chicago Bulls, even though the kids are two or three feet shorter than players in the NBA. I guess we like to create the illusion for ourselves that these youngsters are playing the same game as Michael Jordan.


House rules

Even if Leslie finally figured out exactly how our "rules" differed from the ATP's, he would undoubtedly still be very uncomfortable in our doubles game. For one thing, we play a relatively "casual" game.

We often talk to each other between points, jokingly insult one another, compliment a particularly good shot, ask what the score is, predict what is going to happen next, and so on. Between games, we might exchange personal information or tell jokes.

None of this, of course, happens in professional level tennis, at least not the matches shown on television.

My guess is that Leslie would be disconcerted by our apparent lack of decorum. He would probably perceive us as being remarkably uninterested in the outcome of the game, when in fact we play to win almost as "seriously" as the pros. If he was used to silence between points and games, his concentration might be seriously upset.


Banter protocols

Perhaps he would eventually be able to shrug off our casualness as a trivial idiosyncrasy which doesn't affect the game in any significant way, but it is doubtful that he would be able to participate in the banter. In that case, our "rules" would accommodate his silence. No one is required by our etiquette to talk if s/he doesn't want to, although we (at least I) tend to prefer those with "personality." The game is just not as much fun (for me) with duds or robots.

If Leslie did start to talk, though, he might find himself violating other aspects of our etiquette. Certain subjects are taboo, or at least frowned upon or rarely mentioned. Business, for example, is almost never discussed between points and rarely between games. (Perhaps this is merely because the people I play with don't share work experience.)

More significantly, politics and religion are strictly avoided. At most, someone will make a passing comment about the president or some interesting current event, but I can't remember a single remark about abortion or gun control or any other such controversial topic, even when I have played with other academics. It's as if we do not want to acknowledge that we might have serious disagreements outside the tennis court.

Would Leslie recognize that we are limiting our comments to certain topics? Until I wrote these last sentences, I had never articulated this "rule" even to myself (though I've been playing for over 40 years).


Our own language

Leslie would almost certainly have more difficulty getting used to our line-calling practices. Since we don't have officials, we (like most hackers, I assume) have devised a fairly elaborate system for deciding if a ball is in or out.

Keep in mind that we have never discussed this system, never written it down, never spelled it out in any way, yet our entire game depends on each player's following a fairly rigid, if unstatable, set of behaviors. (I'm willing to bet that is generally the case with most amateurs, including those in tournaments, which rarely have official line-callers).

First, we sometimes use hand signals to indicate "in" (a palm down) or "out" (a finger point), and sometimes, when we think the call is obvious, we say nothing at all. As far as I can tell, we use hand signals only when the ball is not returnable and say "out" when a player has hit the ball back and we wish to indicate that the point is over.

Second, we have a set of "rules" governing which player makes which call. Generally, players on the team about to hit the ball are expected to call the lines, even if a player from the opposing team is closer to the ball when it hits near the line. For example, on a serve, the partner of the player receiving the ball is supposed to announce an out ball.

Of course, there are exceptions (which I can only hint at). Sometimes, for example, the player that hit the ball (or his/her partner) has an unobstructed view of the situation and makes the call. Sometimes, more than one player makes the call. Occasionally two players disagree and a discussion ensues.

To settle a disputed line call, some players like to look for the impression (called a "spot") the ball has left on the playing surface. If they cannot find a spot, they generally assume the ball hit the line (and the point is awarded to the hitter).


Fuzzy boundaries

For the most part, in keeping with the game of "Who's the best sport?", players try to appear calm, rational, polite, and objective about line-calling, but occasionally someone will get upset over another's call, and a new game, whose rules are even harder to describe, breaks out. In this game ("I'm Right and You're Wrong"), the object is to get the other player to back down and agree with your perception.

What players under these circumstances are allowed or not allowed to say depends partly on the social rules that are in operation—the power relations among the players off the court—so once again we see the fuzziness of the boundary between game and non-game.

In most cases, the desire to continue play or to win the sportsmanship game ends an argument fairly quickly (but I remember once when a player and his grandson argued for over 15 minutes about a particular line call). Usually, when an impasse is reached, players will agree to take the point over.

As should be clear by now, I would never get all our practices down on paper, no matter how long I stayed at it. In fact, I haven't even finished explaining our system for calling lines, or the "rules" related to the length of time it's appropriate to debate a particular line call.

In addition, in my attempt to codify our game for "outsiders" (those who have never seen us, or other hackers, play), I have found myself distorting the reality for the sake of convenience. In many cases, I ignored what I knew to be clear exceptions to avoid getting bogged down in impossibly complicated nuances that I'm only dimly aware of.

For instance, one friend, John, and I always discussed controversial issues when we played singles but never when we played doubles! I also ignored the fact that the various groups I play tennis with do not play by identical rules (e.g., normally we spin a racket to determine which team serves first, but when we play at Nazim's house, the player who opens a can of balls serves the first game); only hinted at the effect a change in circumstances (outdoor vs. indoor, free vs. fee) can have on our game; and oversimplified the modifications in our game over the years.