All the choices we have are assigned to us; not by God, but by our surroundings.
Things around us shape what we believe and how we think; just like a cliche we normally say: "We are the average of the five people we spend the most time with."
This means "The Sound in Our Head", or what we call "Thoughts", are the byproduct of our surrounding.
If that's the case, can we really trust the reasons we give? Would it be too early to say that "We have full control over our life because we are the one who choose it?"