Stealing signs: fair or foul? Baseball's on-field intelligence gathering has been going on since the early years of the major leagues.(decrypting signals given by coaches and managers)

IN BASEBALL, THERE IS THE OFFICIAL rulebook, which teaches kids how to play. And there is the unofficial, unwritten rulebook, stored in players' heads and psyches, with boundaries determined only when crossed.

How do you know when you've crossed an imaginary line and broken an unwritten rule?

You just know, that's how. If not, a 90 mph fastball directed at your head serves as enforcement.

And there is one more rule in baseball: The unwritten is always more important than the written.

These things played into the early season flap involving Sammy Sosa, accused by St. Louis Cardinals pitcher Matt Morris, pitching coach Dave Duncan and manager Tony La Russa of stealing signs in a game last May. The Cubs allegedly were figuring out the location of the pitches Morris was going to throw and relaying the information to Sosa.

So Sosa was accused of cheating, even though the rulebook only prohibits signs being stolen by electronic means. And if that's the official rule, the unwritten part is this: It is OK to steal signs by other means.

Otherwise, why not ban all forms of sign-stealing?