Tonight, the darkness will be filled with light. HinduA follower of Hinduism, the third-largest religion in the world. Roughly 95% of Hindus live in India. communities across the world will be lighting candles and letting off fireworks. Meanwhile, in Christian countries, children will be circling their neighbourhoods with torches and lanterns, dressed like witches, wizards, vampires and ghosts.

This evening, two major festivals are taking place. One is Halloween, when people remember the dead and all things supernatural. The second is Diwali, the Hindu festival of lights, when the victory of good over evil is celebrated.

In America, around 70% of the population plans to take part in Halloween.¹ In Britain, two-thirds of people (67%) have done the same at some point.² And, in total, 37 countries around the world mark the festival.³

Meanwhile, around one billion Hindus celebrate Diwali worldwide.⁴ This includes much of the population of India, as well as Hindu communities in the rest of South Asia, Britain and America.

Not everyone who celebrates these festivals is religious. Nonetheless, their popularity suggests the ongoing significance of the spiritual realm. Ideas such as remembering the dead or finding hope in darkness matter to believers and non-believers alike.

In many countries, there are signs that religion is in decline. One recent survey suggested that a third of Americans never attend church, while a majority are unsure about the existence of God.⁵ Meanwhile, in Western Europe, the number of people who never engage with religion is at record high levels.⁶

This trend has been developing over many years. Some would argue that it began in the 18th Century with the Age of EnlightenmentAn intellectual movement of the eighteenth Century that ruthlessly criticised religion, traditions and inherited privilege.. This was an intellectual movement encouraging people to focus on the rational and material world - things they could see, touch and measure scientifically - rather than the spiritual realm.

Many scientists still make the case for Enlightenment principles. Religions often promote old-fashioned ideas about the role of women and the treatment of gay people. They can also fuel hatred between different groups and even inspire violence.

However, other thinkers argue that religious belief makes people happier and healthier. For instance, people who regularly attend church are believed to be at lower risk of depression, anxiety, and suicide, as well as cardiovascularRelating to the heart and blood vessels. disease and death from cancer.

This may be because religion gives people a sense of community or helps them cope in difficult times. Or it may be because churchgoers are less likely to smoke, drink and take drugs. Whatever the reason, the benefit is similar to that of avoiding other "major health risks - like smoking," according to respected researcher Dr Laura Wallace.⁷

Of course, nobody is celebrating Halloween or Diwali for health reasons. But their popularity suggests that people still care about non-material matters, whether it is fears about the past or hopes for the future. And the fact that believers and doubters can both take part in these festivals makes them perfect for the modern world.

Do we all need a spiritual life?

Yes: The material world is made up of things: it cannot provide meaning, morality, or comfort in times of crisis. People need the spiritual realm, whether or not they believe.

No: Nobody can prove that the spiritual realm exists at all. Reason, science and a practical approach to life will bring much more happiness than religion.

Or... Many people believe something but no longer feel comfortable with organised religion. Festivals like Halloween or Diwali let them explore spiritual questions in their own way.

Hindu - A follower of Hinduism, the third-largest religion in the world. Roughly 95% of Hindus live in India.

Enlightenment - An intellectual movement of the eighteenth Century that ruthlessly criticised religion, traditions and inherited privilege.

Cardiovascular - Relating to the heart and blood vessels.