"Acceptance, in spirituality, mindfulness, and human psychology, usually refers to the experience of a situation without an intention to change that situation. Acceptance does not require that change is possible or even conceivable, nor does it require that the situation be desired or approved by those accepting it. Indeed, acceptance is often suggested when a situation is both disliked and unchangeable, or when change may be possible only at great cost or risk. (...) Thus someone may decide to take no action against a situation and yet be said to have not accepted it."
in Wikipedia
Acceptance
When the spent sun throws up its rays on cloud
And goes down burning into the gulf below,
No voice in nature is heard to cry aloud
At what has happened. Birds, at least must know
It is the change to darkness in the sky.
Murmuring something quiet in her breast,
One bird begins to close a faded eye;
Or overtaken too far from his nest,
Hurrying low above the grove, some waif
Swoops just in time to his remembered tree.
At most he thinks or twitters softly, 'Safe!
Now let the night be dark for all of me.
Let the night be too dark for me to see
Into the future. Let what will be, be.'
poem by Robert Frost
