There are times when it is important to leave the present moment.  You may choose to spend time dreaming, visualizing or planning your future.  You may also want to revisit the past to heal old wounds.  Be aware of  spending too much time away from the present moment though since it is all too easy to get lost in obsessive thinking and details.  Set a time limit and mindfully bring yourself back to the present moment.  You will delightfully discover that amount of time you spend dreaming and reflecting can be just as nourishing as living fully in the moment!