As medicine is concerned with maintaining the health of the physical body, so is meditation concerned with maintaining the health of the soul and mind.
You probably noticed the same root prefix, namely medi-, which in turn is turned derived from “medicus” the latin word for physician. Meditation is therefore the healing of the soul, and we all know that a physical organism can be perfectly health from a physical perspective yet be mentally unstable and suffer from depression, severe anxiety or even contemplating suicide.
That being said, medicine makes the body “happy” while meditation makes you happy. Are you merely your body or are you something much more subtle than that?
Meditation means to know yourself and in that knowing healing yourself through clarity of understanding.
P. S. You need not sit down to meditate, or close your eyes. Simply be one with yourself and you are in a state of meditation.
“We alone who meditate know that we are immortal.”