So, let's start with a definition. A dialogue tag is a clause of two words or more which attributes speech to a particular speaker.
"Hello," John said.
Hello is the dialogue. John said is the dialogue tag. The tag makes clear that John is doing the speaking, rather than Mary or Chris or the dining room table. (Forgive me that last one -- I'm currently reading Jonathan Strange & Mr Norrell, a book in which it would be perfectly normal to have a table deliver dialogue. n.b. Alicia -- you were so freaking right about this book. I should have read it the second you recommended it.)
According to our definition, then, there are two aspects to a dialogue tag.
- A speaker
We usually think of a tag as a way to identify who is speaking. But there are many tagless ways to accomplish that same goal. For example, you could use a bit of stage direction:
"My goodness, I'm hungry." Mary laid her napkin in her lap.
In that case, there is no dialogue tag, but the stage direction (Mary laid her napkin in her lap) indicates who the speaker is. This is an effective method for keeping the narrative focused and seamless.
Some of you may already be familiar with the concept of the rule of three -- this notion that the number three comes into play over and over again for good writing. There are two applications of the rule of three to dialogue tags.
First, If you have three or more people speaking in the same conversation, you must find a way to identify the speaker for each and every dialogue exchange. Use a tag or a bit of stage direction, sometimes referred to as a beat.
"What kind of soup is that?" John asked.
"Cream of broccoli." Mary picked up the ladle.
"If it's hot, you'd better get a trivet," the table said.
Second, If you have two people speaking, you can go for three exchanges without any attributions before the reader will start to lose track of who is saying what.
John paused before the closed front door as if reluctant to leave Mary. "Thank you for dinner."
"You're welcome. Sorry about the talking table."
"No, the table was no trouble at all. But maybe next time you'll let me take you out?"
"That would certainly be an aid to good digestion."
Most readers will be able to follow the back-and-forth between John and Mary in the above passage even though three of the quotations are unattributed.
So, your first question when evaluating tags is: can the reader correctly identify the speaker through some means other than a tag? If so, you may not need a tag. But in order to know for sure, you'll have to evaluate the other half of the tag equation.
Because there are generally quotation marks around speech (fuggedabout Cold Mountain for the moment), the reader already has a clear visual cue that the words are spoken aloud. So when we're evaluating the speaks half of the speaker speaks formula, we're not so much concerned with the fact of the speech as with the nature of the speech.
If you want to call attention to the manner in which the speech is delivered, you use a verb tag other than said. If the manner of the speech is unimportant, use said or use another attribution method discussed above. In most cases, the manner of speech will be unimportant.
How do you know when to call attention to the manner of speech? There are two rules of thumb that I can think of right offhand. First, if the delivery method is an important bit of action in the narrative, then the tag verb should relate to that action. For example, if Mary has ignored her family's entreaties to get out of bed, perhaps they send her nine-year-old brother Boris to wake her. In that case,
"Good morning, Mary," Boris shouted.
would give us something relevant to the scene action. Boris is shouting in an attempt to rouse his lazy older sister. If Boris says the words instead of shouting them, the action of the scene is impacted. Right?
Second, if the manner of speech is contradicted by the content of the speech, you'll want a non-transparent tag verb to highlight that contradiction.
"Boris, you'll have to speak up. I can't hear you over all the shouting," Mary whispered.
Mary is being sarcastic, of course, but the sarcasm is made more evident by the dialogue tag.
And now, a pet peeve
This is the part where I rant about all the simultaneous constructions in dialogue tags.
"I refuse to hold that turkey. I'm a vegetarian now," the table said as it eyed the 24-pound bird on the enormous heirloom platter.
If we've already established the fact of the talking table, and if the rule of three allows it, you can and should edit that tag. (Remember -- verbs are gemstones. Set them well.)
"I refuse to hold that turkey. I'm a vegetarian now." The table eyed the 24-pound bird on the enormous heirloom platter.
There are probably other rules of thumb I'm overlooking at the moment, but this ought to be enough to get everyone started on better, cleaner dialogue attribution.