Rabbi Isadore was a wise teacher.
A student asked, "How is one to know the precise time when night ends and day begins?"
One student volunteered, "It is when one can distinguish between a dog and a sheep in the far distance, that is when day begins."
Another said, "It is when you can tell the difference between a fig tree and a date tree, then night is fully gone."
"No, it is neither of those things," said the Rabbi. "It is when you can see your brother or sister in the face of a stranger. Until then, night is still with us."