This famous line from a poem by Percy B. Shelley is frequently quoted whenever a type of situation arises. Winter is considered the time of death. The trees have lost their greenery, and animals are not as active. Winter is tough to survive. What keeps life going is the remembrance of spring, which follows winter as sure as the sun rises in the east. Life has a cycle just as the seasons do. After a time of death comes a time of rebirth and renewal. Spring is the time for this rebirth of life, with young ones being born and plant life budding.  Another quote that follows in the footsteps is, "It's always darkest before the dawn".