People often ask how they can avoid daydreaming when they are trying to meditate. Meditation does not make them daydream, but only makes them more aware of fantasies they have always had. In meditating even for a short time, they hold a mirror up to themselves that clearly reveals the shape of their fantasies.
Walking deep in a forest in late autumn, you may be startled by the loud rustling of your feet among the dry leaves breaking in the stillness. Fantasies disturb meditation in the same way.
~ from "The Sound of Our Own Footsteps" by Shundo Aoyama