"Words... They're innocent, neutral, precise, standing for this, describing that, meaning the other, so if you look after them you can build bridges across incomprehension and chaos." -Tom Stoppard
One of the first, if not the very first, things that Sherlock learned was that words were important.
They were power.
And before he even learned how to wield his words, he learned just how precious they were.
Mummy and father would go around talking about it, how so and so had run out of words, and oh dear how could the queen possibly manage.
So in a way that only a very young mind could, Sherlock concluded that words were something to be careful used, only when it was necessary. Because otherwise, you might run out.
So that was the reason he didn't speak until he was five. It was only then that he could grasp the concept that yes, words were important to keep, but were also so incredibly important to use. And that even if he said something, that wouldn't be the end. There would still be enough to say something else, again and again, for a while anyway.
After all, when he first spoke, after all those years and doctors and examinations, they had an almost magical effect.
Sadly, it didn't always work like that, Sherlock learned. It seemed his newfound power was largely due to the shock value that him speaking provided.
Words did have power, but Sherlock would have to hone those skills in order to make the most of his limited (and oh god he was so limited) number of words.
By the time he was ten, he found that some words had more power than others. Some words were apparently not acceptable to use. Sometimes one word could say what a dozen others could not. Sometimes words meant nothing without context, without the safe cushion that was paragraphs and sentences.
It was also around that time that he realized everyone was limited by words. Everyone had that countdown embedded in their DNA, that would limit them, limit the power they had.
So it was a matter of using words to the best of their ability, and it was clear that some could do it better than others.
Sherlock had nightmares where he watched in horror as the count ran down to zero, and no matter how hard he tried, there were no words. No matter what. He called for help, and nothing came out. No one came.
The mornings after had had those dreams were very quiet.
Of course, it wasn't a matter of watching the countdown where it was embedded on his skin, because that would be too easy. Rather it was a once a year thing, hardly cause for celebration, but often was, because it occurred on the same day as your birth.
It was a biological birthday present, although it often wouldn't seem that way. Sherlock hated his birthday for that reason, a reminded of how much was slipping away every year.
He would rather die than run out of words.
So as he grew older, moved out, he played fast and loose with life, but kept his words close to his heart, tucked away for only the most important things.
Then came Lestrade and along with him consulting work and then came John.
He wasn't sure what it was about John, such an ordinary man at first glance, but Sherlock had an overwhelming urge to share his words with him.
(Was that love?)
It was different for everyone, where the counter was. The wrist was a common place for it, as was the upper arm. It was rare to find it somewhere that was constantly visible, like the face. Apparently biology was relatively kind recognizing that it was something private, and should be able to be kept hidden.
It took him a while to find out where John's was, and once he did find out, he knew why. It was on his chest, directly above his heart. He hadn't seen it before because that would require John removing his shirt, which would reveal the scar from the bullet wound. Sherlock didn't understand why he would be ashamed by a scar, since it was more a trophy than a curse, but not everyone thought like him.
Mycroft's was on his shoulder, typical. Mrs Hudson's was on her wrist, which she made look elegant. Molly's was on her forearm, and Sherlock did worry for her. She said so little with so many words. If she got rambling he would silence her with a warning of her name, and that usually made her pause to think about what she was actually saying. (He did what he could.)
Sherlock's was between his shoulder blades. He couldn't see it without a mirror or two, and then it was backwards. He quickly became proficient in reading backwards, upside down, or both. It was a skill that paid off in his other work, and also just generally provided amusement.
Sherlock dreaded the coming of January, both hating the day the number would change, and also fascinated in a morbid sort of way.
It was almost like a countdown to his death.
(Because he certainly wasn't going to live without them. He decided on that a long time ago.)
Sherlock envied John, how the words came so easily to him, how he was so willing to give them away, to soothe another.
He would whisper to Mrs Hudson as he cleaned her cuts, and he would speak softly to the unconscious people who weren't even listening, and he would look at Sherlock while he emerged from his mind palace and asked him if he was okay.
John Watson gave his words away freely, and still had so many.
Sherlock didn't understand him.
John's birthday came and went. Sherlock didn't entirely forget, but John went out with the girlfriend of the month, and Sherlock would rather forget both of those things than remember John's birthday and the fact of his dating life.
Lesser of two evils.
Sherlock wondered where John stood, in terms of his number.
He managed to sneak a peek a few days later. (There might have been some spilling of beverages. John sighed and gave him a look like he should have just asked.)
"How do you have so many?" Sherlock asked after John had changed out of his wet shirt.
His counter seemed to have barely budged since the last time Sherlock had seen it. (Of course he took note, this was John.)
John only smiled and shrugged. He knew what Sherlock was asking about.
"I may not be as stingy with my words as you are, but I know they're important, and are something to be cherished."
Sherlock sighed. "I don't understand. Why do you seem to not care about wasting them?"
John smiled even larger.
"You don't get it, do you?"
Frustrated, Sherlock shook his head.
John laughed softly. "Yes, words are important. They are something to be cherished and kept close, to be savoured and counted and used sparingly. But words are also for sharing. That's why we have language, why we have words that can say something like 'a yearning for something you loved and lost, or has gone away.' There's a single word that we have to say that, you know. Words were made to be shared, Sherlock. I'm surprised it took you so long to see it."
Sherlock frowned. "What if you run out?"
John shook his head. "Maybe I will. But it will have been worth it."
Sherlock leaned back in his chair and steepled his hands beneath his chin.
"Perhaps," he murmured.
John could tell he still wasn't sure.
"Alright then. Answer me this, Sherlock Holmes. What's going to happen when you get to the end of your life, your ridiculously long life, because you know that's going to happen. If nothing has killed you yet, nothing will except old age, or maybe stupidity on your part."
Sherlock scowled when he said that, but no argument could be made against it. Not from the man who passed out because forgot to eat. Twice.
John continued. "So what's going to happen when you get to be old and grey and wrinkled, and there's no one around to listen as you try to use them all up. What are you saving them for?"
Sherlock pondered that for a moment, and when it did come to him, it did so with a burst of lightning announcing its presence.
Oh... his mind exhaled.
Sherlock didn't know how he'd been such an idiot, for so long. Because when John pointed it out, the answer was simple. Obvious really. And he told him.