“My mind is preoccupied with past thoughts.”
The ego mind regurgitates thoughts that have been thought, over and over again. Even when you think that a recurring monkey thought is about the future (as in worry or in dread), its basis lies in the past that you believe happened. It may be clear that those types of thoughts are in no way sufficient to live the present moment to the fullest.
The course is helping you to see the restriction you put upon myself by entertaining and believing the random thoughts the monkey mind regurgitates, if you let it.