"Balance" when talking about the Force.
First off, let me preface this by saying the best explanations I've seen about the concept of Balance of the Force are the below two:
What follows is simply my way of explaining "the Prophecy of the Chosen One who will bring Balance to the Force"... with diagrams!
(Quotes I used as sources can be found at the bottom of the post.)
On that note: let's get cosmic!
I. The Living Force's natural state.
The Force has two aspects.
- The Living Force, generated by all living beings, which in turn powers the wellspring that is...
- The Cosmic Force, which then binds everything and speaks to us via the midi-chlorians. The Cosmic Force has to do with destiny.
The term “Balance of the Force” refers to the Living Force’s natural state... balanced. As seen below:
On one side, you have one BIG cog. That’s the Dark Side.
- The Dark Side is empowered by all evil. Every act of selfishness, violence, corruption, sadistic pleasure, etc.
- Be it a criminal shooting an old lady to a politician embezzling funds and letting his constituents starve. From the Nightsister, to the pirate, to the Hutt, to the corrupt senator.
- By its very nature, the Dark Side will consume everything in its path if it's overfed, just like a flame will turn into an inferno.
On the other side, you have a lot of small cogs. That’s the Light Side.
- Empowered by all that is good, every young boy helping his little sister, every mother going hungry so that their child can keep on living, every selfless act of generosity, every joyful laugh, etc.
- From the Jedi, to a benevolent Queen, to the civilian working at a soup kitchen.
- By its very nature, the Light Side serves the Force's will.
You need a lot of good cogs to balance out that one bad cog. Why? Because being an asshole is easier, and more people choose the easy way over the hard way, in the galaxy. It takes many good deeds to make a difference and one bad one to make it all go up in flames.
Neither Side is either benevolent or malevolent. The Dark and Light Sides are non-sentient metaphysical aspects of the Living Force, they're not good or evil, they just are. And, for better or for worse, they're both essential to have Balance.
So where's the issue?
II. The Force at the start of the Prequels.
The issue is that the Dark Side has been growing more and more. This is causing the Force to gradually become unbalanced.
The Republic has grown corrupt, the Jedi haven't but they've become its lapdogs. More and more senators and bureaucrats take bribes, the crime lords and slavers grow more ruthless, corporations become increasingly power-hungry... and a phantom menace seems to be speeding up the clock for when this will all go to hell.
That phantom menace is the Sith. More specifically, Darth Sidious.
The Sith are literally the galaxy's only order of Force-sensitives who constantly use the Dark Side to make the Force submit to their will, rather than following the Will of the Force. Their endgame is to be to control everything, Balance be damned.
And they're winning. The Force's few remaining champions, chiefly the Jedi, are completely unprepared in the face of this threat.
So the Force retaliates and creates a Chosen One, destined to destroy the Sith: Anakin Skywalker.
That’s it, that’s his destiny, as dictated by the Cosmic Force: destroying the Sith, thus bringing Balance.
Just one problem... at the end of Episode I, Sidious gets elected Chancellor and essentially is put in charge of the whole galaxy.
The Sith have as good as won.