Humans began burying objects with their deceased loved ones long before anybody started recording history.

Archaeological excavations of the Qafzeh and Skhul Caves in Israel have discovered graves dating back as far as 100,000 years that contain grave goods such as flint artifacts, animal bones, seashells and lumps of red ochre. Fast forward 75,000 thousand years and burials included decorative clothing, jewelry, weapons, animal carvings and other ornamental objects.

Although there are a number of possible reasons for why we started to bury objects with the dead, evidence suggests these objects were meant to accompany the deceased in the afterlife.

Grave Goods: Gifts for the Afterlife

The Egyptians, for example, even buried their dead with maps and food. 

In Rome, they used to bury their dead with a coin for Charon (the ferryman to the underworld). And the Chinese have a history of burning paper money and precious objects for the dead to take to the afterlife.

Today, despite a spectrum of beliefs about the existence of the afterlife, people continue to participate in the practice of leaving meaningful objects with the deceased. But why?

The grave goods trend has led some to posit that humans have an innate predisposition to believe in the afterlife.

Read More: How Ancient Egyptians Preserved Bodies for the Afterlife

Challenges to Afterlife Theories

Notably, however, typical Christian burials have historically included few or no grave goods, posing a problem to the afterlife hypothesis.

Additionally, some “extinctivists” in Western countries — meaning, people who believe the soul does not continue after death —  are known to leave grave goods with the deceased.

This reality seems to pose a problem for the prevailing afterlife theory. Or does it?

A March paper published in Cognitive Science digs up some nuance on the matter, while supporting something called the “afterlife use” theory — the idea that grave goods are useful to the deceased with either emotional or physical benefit.

Clues of Afterlife Beliefs in Graves

In that work, psychologists from the University of Otago in New Zealand investigated the role of explicit and implicit afterlife beliefs in the context of grave practices.

Explicit beliefs refer to what we say we believe, in this case when asked about the afterlife. Implicit beliefs, on the other hand, refer to how we behave or intuitively reason when it comes to making choices regarding death and the afterlife. 

In a series of three studies, which compared participants from the U.S. and New Zealand, researchers asked subjects about their grave practices in actual and hypothetical funerals.

The findings show that jewelry, photographs and other meaningful items were commonly left with deceased loved ones.

They also reveal that people’s intuitive afterlife reasoning (as measured by attributions of mental states to the dead) motivated grave practices for about half of the study’s participants, while those who held explicit afterlife beliefs were also likely to participate in the practice.

Read More: When Did Ancient Humans Begin to Understand Death?

Envisioning Absence of Consciousness

The researchers argue that despite the self-reported lack of afterlife beliefs on the part of extinctivists, most people hold implicit beliefs about the afterlife.

That is, they are psychologically predisposed to picture themselves and their loved ones as continuing to exist as mental agents to some degree after death.

This is in part due to the difficulty for humans to properly envision death as a psychological end, or what psychologists refer to as a “simulation constraint” on the human ability to picture death as an absence of consciousness.

“People have a really tough time trying to think about their deaths. The only experiences we can draw on to imagine death are conscious ones, but death is the complete absence of consciousness,” says experimental psychologist and co-author of the study Jesse Bering.

Beyond Reason

A significant body of research has highlighted discrepancies between what people say they believe and how they act or reason about the afterlife.

For example, in a previous study by Bering, individuals who identified as extinctivists still assumed that a dead person would retain psychological capacities (e.g., they would have some awareness that they were dead).

In another study, psychologists found that extinctivists were reluctant to sell their soul to the experimenter, even when told the contract was not legally binding and would be shredded.

Individuals, from another study, who were casually informed about the presence of a ghost in a laboratory were less likely than control participants to cheat on a competitive task when left alone.

Limits of Our Self-Awareness

The cumulative results suggest that even though a significant percentage of humans explicitly reject the existence of an afterlife, it is likely our evolved self-awareness has made it difficult for us to realistically perceive existence after the cessation of our conscious selves.

As such, perhaps some of us can’t help but imbue the deceased with conscious faculties, resulting in the continued practice of leaving treasured goods with the dead. 

Read More: Can Science Explain Near Death Experiences?