Over the years while teaching at The Beekman School, I’ve come across a common misconception my students have about meditation. They see it merely as a passive act of relaxing and letting go of all thought. While those may be aspects of the end result of the practice, historically there is nothing intentionally passive about meditation. The etymology of the word itself is “to think” and has always been understood that the process is a very active engagement with the mind.
Meditation comes in many forms which intend to achieve seemingly various goals. Traditionally, though, the goals of these practices were towards some transcendent experience of a communion or an absorption in the divine - an unchanging noumenal reality. The process to achieve that is by learning to control and focus the mind.
Often students who misunderstand what meditation practice is will complain about experiencing sleepiness when they meditate. Barring exhaustion, if practiced correctly (as traditionally prescribed) this should not occur. The general methods that have been used for centuries are sound (or word) repetition, concentration on a point that resides inside or outside the body, and focusing on an abstract concept -- a lot of effort in order to remove stray thoughts, thus conditioning the mind. The conditioned mind frees the individual from himself and opens the way to that greater experience of life that the ancient practitioners sought. Instead of succumbing to the low consciousness level of sleepiness, the proper meditator enures to a higher state of consciousness.
Meditators who merely relax and let go their thoughts are only well-rested. Meditators who work at changing the way their minds operate will achieve clarity and greater insight. To read more about the various traditions, their practices and goals, visit the Wikipedia page below.
https://en.wikipedia.org/wiki/Meditation