Look in your family photo album and what do you find? Pictures of graduations, birthday parties, weddings and vacations. Photos taken during holidays celebrating the new life of spring, the return of the sun in mid-winter, fruits of the harvest.

Everyone is smiling, no matter how much tension lurks behind the pleasant façade. Where are the images of break-ups, divorces, illnesses, and funerals? These events shape us as much as, perhaps more than, the happier moments. But we hide them away, preferring a story that life is all about joy.

That's why Halloween is so important: it is the only holiday that commemorates death, offering us a rare opportunity to face the darkness. Not the darkness of violence or evil, but the darkness that is part of the natural cycle: a chance to accept endings, to mourn losses and to recognize our mortality.

A century ago, most people died at home and were laid out in the front parlor. But now death is something we rarely witness, except the violent deaths depicted on TV shows, in films and in crime novels. As a society, we cling to the myth of perpetual summer, constant growth in the economy, and continuous improvement in our personal lives. So when things go wrong, when we make mistakes, when we lose someone dear to us, we see that as abnormal.

We confuse darkness with evil, and approach death with fear, thus the emphasis in American celebrations of Halloween on demons and ghosts, the gory and the grotesque.Yet death is as natural as life.

All cultures have a holiday when the dead are honored--in fact, most have more than one: In Japan, the Obon festival in July; in China, the Moon of the Hungry Ghosts; in ancient Rome, the ghosts of the ancestors were appeased during Lemuria on May 9.

Today in America, we still have the secular holidays of Memorial Day and Veteran's Day. But during my childhood, those perfunctory trips to the cemetery to lay flowers on my grandfather's grave never caught my imagination the way Halloween did, and still does. Underneath the disguises, trick-or-treating and parties, the spiritual heart of the holiday is an acknowledgement of death.

Halloween is a complex blend of customs from many different cultures and holidays. The oldest layer comes from the Celtic festival of Samhain, which means "summer's end." It was also the new year--the Celts believed the year began in darkness, just as the day began at dusk. It was a time when the crack between this world and the Other World was open. Fires were left burning during the night and people avoided walking in isolated places, for fear the fairies would take them away. In Ireland, the whole month of November is devoted to the dead, who hold their final dance on November 30.

In the seventh century, the Catholic Church established a holy day honoring All Saints. At first celebrated in May (when the Romans held their feast of the dead), it was later moved to November 1. Also known as All Hallows Day, it's the source of the name Halloween (the eve of Hallows). By the 10th century, the following day, November 2, was officially designated as All Souls Day, when the faithful pray for the souls of their departed.

The Cathars, who developed a unique Christianity that flourished in Southern France until wiped out as heresy by 13th century Crusaders, believed that this was the day when the souls of those who died during the year entered into a place of rest. Before this day, they wandered around the earth, from church to church. Angels chose from this flock those ready to be admitted. The living could influence the selection by saying Masses for the dead, paying off their debts and giving gifts to the poor.

This is similar to the English tradition of going from house to house, gathering ingredients for soul-cakes. Sometimes these were left out for the poor to eat, sometimes given to the priest to pay for Masses for the souls of the dead, sometimes given to "sin-eaters," beggars who took on the sins of the dead.

Although the emphasis in the church was on praying to the saints (the holy dead) and for the souls of those in purgatory, we can glimpse an earlier understanding that this was a time that the dead returned to visit their families in the way Italians celebrate I Morti. On the night of November 1, before they go to bed, children set out letters they've written to their dead relatives, along with a list of presents they want. The dead rise up from their graves and roam through the streets, drifting like smoke into the stores, stealing sweets and toys to leave as treats for the children. When the children wake up on November 2 they search for these presents and shout out thanks to the ancestors when they find them.

When the Spaniards brought this Catholic holiday to Mexico in 1521, it went through another colorful permutation to become Dias de Muertos. The indigenous people of Mexico did not fear death like the European Christians for whom it was a time of judgment. Instead, they viewed death as a phase in a cyclic journey: to die was to wake from the dream of life.