My theory on what exactly is the smoke monster by Volchok

There's always been a lot of talk about what the smoke monster is and now we know a lot more about him then we did in the first seasons of the show. And yet, there's still a lot of room for speculation.

Some people think Smokey (let's call it that) is an entity of itself. An entity that was released when the man in black (samuel) entered the cave. This entity then used the image of Samuel and later on the image of Locke.

I disagree with this theory and I have an idea of what the smoke is. It might not be right but it makes sense and I like it.

Remember when Dogen said that there's darkness and light inside everyone? And that's something the show has always hinted about. No one is purely evil and no one is 100 per cent good.

So, I think that when samuel was pushed into the cave by jacob, and touched/ had contact with the light, he lost the light inside of him. I think the smoke is Samuel's soul without the light. He only has darkness inside of him and that's why his true form is now smoke.

And by the way, I don't think he was evil before that. In fact, I think Mother and Jacob's actions forced him to be evil.

Just a thought. Let me know what you think.