In a spiritual sense, they are (spiritual) facts. We all know what love is but we cannot put it in words adequately or all inclusively, we cannot give a shape, color, dimentions. Love and mercy did not come from the rocks or the clouds. It is something we don't encounter in nature, where necessity justifies everything.
I can... Love is exactely and expressly sacrifice..
Whatever you love you will sacrifice for..
Whatever you do not love you will not sacrifice for..
Sacrifice(love) is in degrees. Love is not a feeling its a deed..