The body has various cycles:
# Hunger cycles = EARTH ELEMENT
# Thirst cycles = WATER ELEMENT
# Sleep cycles = ETHER ELEMENT
# [Sights, Sounds] consumption cycles = FIRE ELEMENT
# In-breath cycling = AIR ELEMENT
# Poop cycles = EARTH ELEMENT
# Urine, Sexual cycles = WATER ELEMENT
# Exercise/Activity cycles = FIRE ELEMENT
# Out-breath cycling = AIR ELEMENT
# Waking state awareness cycles = ETHER ELEMENT
The elements part may not be exact, but I used my intuitive feel to arrive at them.
The body belongs to the earth, and is made up of the earth.
It is an organic machine, built from the elements of the earth, and on death, this entire body machine will be returned to the earth (which will cycle the elements back into itself).
The body emerges from the earth, gathers earth elements onto itself and grows, maintains and renews itself periodically from various elemental transactions with the earth, and then once its time is over, the earth reabsorbs the body back into itself.
The mothers womb provides the initial body as a template, that then separates from the mother, gathers on the elements (what we call growth), and then stabilizes itself in transaction with the elements of the earth.
“On death, the earth will take back the body, atom by atom” – Sadhguru
I have heard Sadhguru(Jaggi Vasudev) on Youtube speak about this topic many times, but only now I feel like I understand it more deeply.
So from the body’s perspective:
It cares about: food, water, sleep, sex, breathing, preservation.
Each of these activities give pleasure, but only as per the cycles.
The pleasure from the body is limited to the cycles only.
When you are hungry you can only eat until the hunger is satisfied, only till then will you get pleasure.
The same holds true for thirst, sex, and even the breath.
Breathing in is pleasure until you get full, breathing out is pleasure until you get empty.
Since all of the elemental transactions are in a cycle, neither can you preserve, nor can you indulge.
It is like your breath.
You can’t endlessly breathe in, neither can you endlessly breathe out.
In terms of source energy, the highest tangible conception of that for us, is the “Sun”.
But we can use only a fraction of that energy directly, and we need all its other stored forms available on earth to survive/thrive.
Sun -> Plants
Sun -> Plants -> Animals
Water -> stores the heat energy of the sun (else without the sun it would turn into ice).
And then we further cook the plant/animal material in fire, and then we have “energy and elements” in a form that we can easily consume.
The earth itself maintains its temperature from the sun.
The core of the earth is almost like a micro sun.
Human bodies are like the most developed neurons(brain nerve cells) of the earth.
Also with only one half of the earth facing the sun at any given point of time, and with the earth constantly rotating, it is always cycling through duality.
Though the sun(source) is ever present, ever radiant, it is eclipsed from influence and view during the night.
So I would think that is why, in the microcosm of our bodies too, we have the sleep and waking cycles which is a correlate to this macrocosmic duality.