A rite of passage
In agricultural societies, as in many traditions around the world, life is not separated from death. It is a very interesting and in so many ways a very healthy view of death, which westerners find so difficult. Most Americans are scared of death and don't even want to talk about aging.
The return of the deads
The Celts believed that when people died, they went to a land of eternal youth and happiness called Tir nan Og. They did not have the concept of heaven and hell that the Christian church later brought into the land. The dead were sometimes believed to be dwelling with the Fairy Folk, who lived in the humerous mounds or sidhe (pron. "shee") that dotted the Irish and Scottish countryside.
Samhain was the new year to the Celts. This was the time when the "veil between the worlds" was at its thinnest, and the living could communicate with their beloved dead in Tir nan Og. In addition to the fairies, many humans were abroad on this night, causing mischief. since this night belonged neither to one year or the other, Celtic folk believed that chaos reigned and the people would engage in "horseplay and practical jokes". This served also as a final outlet for high spirits before the gloom of winter set in.
A modern catharsis
Man is also is sometimes govern by his bad instincts, stealing, killing or doing whatever harm. One of the best ways, one that has worked for thousands of years, is to express them harmlessly by acting them out in pretense or in play. This recognition of the worst in us seems to lessen its power. The ancient Greeks called this catharsis.
Our worst selves must be recognized in order to be controlled. Now, more than ever, we need to fill our streets with ghosts and goblins, lurid skeletons and other horrifying incarnations of evil.
The quintessential symbols of Halloween fall into three major categories. Symbols of death include graveyards, ghosts, skeletons, haunted houses. Symbols of evil and misfortune are witches, goblins, black cats. Symbols of harvest are pumpkins, scarecrows, corn shocks and candy corn.
The first two categories tap deep, irresolvable, pan-human dilemmas. Ways of dealing with and symbolizing death and evil are represented in some of the earliest archaeological remains of human ritual activity. One traditional means of facing the reality of death is to view it as a transition and to continue a relationship with the dead.