The master once asked his disciples, how exactly the end of the night can be discerned from the beginning of the day.
One answered: “When you see an animal in the distance and recognize it as a cow or a horse.”
“No,” said the master.
“When you identify a tree in the distance as a cherry tree or a beech tree”.
“Wrong again”, said the master.
“When you can differentiate between a hawk or a crow flying above.”
“That too is not the correct answer”, said the teacher.
“What is it then?” asked the disciples.
“When you look into the face of a man and recognize your brother in it. When you look into the face of a woman and recognize your sister in it. Whoever is not capable of that – for him it is night, regardless of where the sun is at that time.”
Paungger & Poppe - Wisdom of the Ages 