Water passes through a selectively permeable barrier.
It is not the most romantic process,
But it shows the cell accepts the water.
It is coveted and important.

A lone oil molecule,
Something left over,
Knocks at the cell’s barrier.
No door opens.

Inside, the water is coveted and important.
Outside, the oil is unwanted and alone.
‘Who decides?’ The oil wonders.
The hydrophilic chemicals are the gate keepers.

Who chose them to be the chosen ones?
Who let them decide?
Nature.
Nature is the creator of all things coveted and important.

The oil knows that if the barrier were flipped,
It’d be let in.
Hydrophobic chemicals are on the other side.
The chemicals of love and hate are attached end to end.

The oil may continue knocking,
But no one will let it in.
It wonders if nature intended to leave it outside in the cold
Or if it just forgot about it.

Outside the school doors,
The weary student considers the process of osmosis.
He considers the barrier around the popular lunch table
And wonders if he were water, would he be let in?

Even nature knows the term ‘exclusion’.