Thoughts. There are many types of meditation out there so it is impossible to say which one is right but instead, pick one that is right for you.
Some people try to clear their heads by allowing no thoughts enter and if they do they quietly dismiss it and go back to clearing their mind. In this emptiness and clearing answers and ideas come to them easier.
Others treat meditation as a brain-storming session and only focus on the end result or outcome and let ideas come to them one at a time while quietly dismissing or categorizing ideas as they come along.
Both of these meditations’ goals are similar to the quote. They both have the goal to control your thoughts instead of letting them control you.
“If you don’t control your thoughts, they will control you.”