A dream within a dream

How sure can we be about reality? Is what we' re living true or is it just a dream within another dream? At times I wonder and I try to define reality but then I'm lost because I simply cannot. After all everything is so subjective and never we will be in other people's shoes...

Maybe we are parts of a larger dream, probably puppets. Some one else is pulling our strings and we perform. All is an act, the world is a stage and we were chosen to participate in it though I cannot understand the reason why.

If we have a purpose probably it will be to find a way to survive and get out. But out where?