Each action, each decision leads to another decision and another action.
Often, there will be an unfathomable amount of decisions for a situation which all have an unfathomable amount of decisions based on the outcome of the decision.
But I digress.
The point, ladies and gentlemen, is that while sometimes there are millions and millions of decisions for a situation that could shape our world, sometimes there are only a few.
And sometimes it is simply a choice between option A or option B.
Unknown to the inhabitants of this world, the day that Doctor John H. Watson walked through the park and ran into Mike Stamford, a choice was to be made.
A simple choice really. But with outcomes that would affect the world, perhaps not each individual country and person, but certainly many countries and many more people.
Sitting on the bench Stamford had a choice.
He could, after John had stated his disbelief that someone would want to share a flat with him and he in turn answered he was the second person to say that, finish his coffee and say his goodbye's and think nothing more of it.
Or he could introduce John to a man he did not particularly like or enjoy being around that much to see if he would want to share a flat with him.
In his mind the consequences for both actions were:
A) Life would go on as usual and the bother of traveling back to St. Barts and purposefully seeking out Sherlock Holmes saved. It certainly seemed much more desirable.
B) He could introduce his former acquaintance to Sherlock and see how everything panned out. It was more effort but it could be interesting to see how long John lasted around the often insufferable man.
Humans have the astounding ability to completely miss the impact their actions may have in the long term.
The Earth, however, saw the consequences for the two decisions in the long term and shook with panic.
A) Doctor John H. Watson would take his life in the small hours of the morning not eight hours after talking with Stamford. Sherlock Holmes would overdose on cocaine two months later. Moriarty's empire would expand, causing grief and destroying lives whenever he felt so inclined. Great disasters, terrorist attacks, toppled governments and eventually London would fall. It would fall hard and never rise again.
B) The two men would forge a friendship so strong no force was great enough to stop them. Through careful planning and a faked death Moriarty would fall and then his followers would be hunted down one by one until there was nothing but ashes left of his empire. The world would always have pain, but those two men would save a considerable amount of it. Despite their dangerous life they would both have an exceptionally long life and, disregarding three long and hard years, would rarely leave each others sides.
Crossing its metaphoric fingers, The Earth hoped and prayed that Stamford would take the time and effort to introduce the two and at the same time cursed humanities incessant need to cut down the amount of effort it wanted to use for itself.
So when John Watson and Mike Stamford walked through those doors at St Barts, Stamford introduced John to Sherlock, The Earth breathed a sigh of great relief.
It was hard enough to worry about the two friends when she had that asteroid that was going to hit in sixty years to keep her busy.