You and everyone you’ve ever known will someday die. According to some psychologists, this uncomfortable truth constantly lurks in the back of our minds and ultimately drives everything we do, from choosing to attend church, eat vegetables and go to the gym to motivating us to have children, write books and create companies.

For healthy people, death usually lurks in the back of our minds, exerting its influence on a subconscious level. “Most of the time, we go through our days unaware, not thinking of our mortality,” says Chris Feudtner, a pediatrician and ethicist at the Children’s Hospital of Philadelphia and the University of Pennsylvania. “We cope by focusing on the things more directly in front of us.”

What would happen, though, if the ambiguity surrounding our own demise were taken away? What if we all suddenly were told the exact date and means of our deaths? While this is, of course, impossible, careful consideration of this hypothetical scenario can shed light on our motivations as individuals and societies – and hint at how to best spend our limited time on this Earth.

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First, let’s establish what we know about how death shapes behaviour in the real world. In the 1980s, psychologists became interested in how we deal with the potentially overwhelming anxiety and dread that come with the realisation that we are nothing more than “breathing, defecating, self-conscious pieces of meat that can die at any time”, as Sheldon Solomon, a psychology professor at New York’s Skidmore College, puts it.

Terror management theory, the term Solomon and his colleagues coined for their findings, posits that humans embrace culturally constructed beliefs – that the world has meaning, for example, and that our lives have value – in order to fend off what would otherwise be paralysing existential terror.

In more than 1,000 peer-reviewed experiments, researchers have found that, when reminded that we are going to die, we cling harder to foundational cultural beliefs and strive to boost our sense of self-worth. We also become more defensive of our beliefs and react with hostility to anything that threatens them.

Even very subtle nods at mortality – a 42.8 millisecond flash of the word “death” across a computer screen, a conversation that takes place within sight of a funeral home – are enough to trigger behavioural changes.

When reminded of death, we become more contemptuous of and violent toward people who are not similar to us

What do some of those changes look like? When reminded of death, we treat those who are similar to us in looks, political slant, geographic origin and religious beliefs more favourably. We become more contemptuous and violent towards people who do not share those similarities. We profess a deeper commitment to romantic partners who validate our worldviews. And we are more inclined to vote for heavy-handed charismatic leaders who incite fear of outsiders.

We also become more nihilistic, drinking, smoking, shopping and eating in excess – and we are less concerned about caring for the environment.

Should everyone suddenly learn the date and means of their demise, society could – and likely would – become more racist, xenophobic, violent, war-mongering, self-harming and environmentally destructive than it already is.

This isn’t pre-ordained, however. Researchers like Solomon ultimately hope that, by becoming aware of the expansive negative effects that death anxiety triggers, we might be able to counteract them.

In fact, scientists have already recorded a few examples of people bucking these general trends.

Buddhist monks in South Korea, for example, do not respond this way to reminders of death.

Researchers looking into a style of thinking called “death reflection” also have found that asking people to think not just about death in a general, abstract way, but to think about exactly how they will die and what impact their death will have on their families, elicits very different reactions.

In that case, people become more altruistic – willing, for example, to donate blood regardless of whether there is a high societal need for it. They are also more open to reflecting on the roles of both positive and negative events in shaping their lives.

Given these findings, learning our death date may lead us to focus more on life goals and social bonds rather than responding with knee-jerk insularity.

This would especially be true “if we promote strategies that help us to accept death as part of life and integrate this knowledge into our daily choices and behavior,” says Eva Jonas, a psychology professor at the University of Salzburg. “Knowing about the scarcity of life may increase the perception of life’s value and develop the sense that ‘we’re all in the same boat’, promoting tolerance and compassion and minimising defensive responses.”

Morbid personalities

Regardless of whether society as a whole takes a nasty or nice turn, how we would react on an individual level to knowledge about our death would vary depending on personality and the specifics of the big event.

“The more neurotic and anxious you are, the more preoccupied you’ll be with death and unable to focus on meaningful life changes,” says Laura Blackie, an assistant professor of psychology at the University of Nottingham. “But on the other hand, if you’re told you’ll die peacefully at 90 in your sleep, then you might not be that motivated to engage with it, either – like, ‘Oh, that’s fine, carry on.’”

Whether life ends at 13 or 113, though, studies of terminally ill individuals can shed light on typical responses to death.

Palliative care patients, Feudtner says, often experience two phases of thinking. First, they question the very premise of their diagnosis, asking if death is definitely imminently inescapable  or whether it is something they can fight.

After that, they contemplate how to make the most of the time they have left. Most fall into one of two categories. They either decide to put their whole energy and focus into doing everything they can to beat the illness, or they opt to reflect on their lives and spend as much time as possible with loved ones doing things that bring them happiness.   

The same processes would likely play out under the hypothetical death date scenario. “Even if you know you have 60 more years, eventually that lifespan is going to be measured in just a couple years, months and days,” Feudtner says. “Once that clock winding down becomes too close for comfort, I think we’d see people moving in these two different directions.”

Those who opt to try to thwart their deaths may become obsessed with avoiding it, especially as time runs out. Someone who knows they are destined to drown might incessantly practice swimming so they can have a fighting chance at survival, for example, while someone who knows they will die in a traffic accident may choose to avoid vehicles at all costs.

Others, however, may go the opposite route – trying to cheat their predicted death by attempting to end their lives on their own terms. This would allow them, in a way, to gain control over the process. Jonas and her colleagues found, for example, that when they asked people to imagine that they will suffer a painful, slow death from an illness, those who were given the choice of a self-determined death – to end their life in a way of their choosing – felt more in control and exhibited fewer defensive biases related to death anxiety. 

Those who go the route of accepting their death sentences may likewise react in a variety of ways. Some would be energised to make the most of the time they have, rising to greater heights of creative, social, scientific and entrepreneurial achievement than otherwise would have been possible. “What I’d like to think is that knowing our death date would bring out the best in us, that it would give us the psychological latitude to be able to do more for ourselves and for our families and communities,” Solomon says. 

Indeed, there is promising evidence from trauma survivors that having a sense of the limited time we have left can motivate self-improvement. While difficult to collect baseline data for such people, many insist that they have changed in profound, positive ways. “They say they are stronger, more spiritual, recognise more positive possibilities and appreciate life more,” Blackie says. “They come to the realisation that, ‘Wow, life is short, I’m going to die one day, I should make the most of it.’”

Not everyone would become their best selves, however. Instead, many people probably would choose to check out of life and cease to contribute meaningfully to society – not necessarily because they are lazy, but because they are overtaken by a feeling of pointlessness. As Caitlin Doughty, a mortician, author and founder of the Order of the Good Death, a death acceptance collective, puts it, “Would you be writing this column if you knew you were going to die next June?” (Probably not).

So much of our culture is designed around staving off death

Feelings of pointlessness may also cause many people to give up any semblance of a healthy lifestyle. If death is pre-ordained at a certain time no matter what, “I’m not going to bother to eat organic food anymore, I’m going to drink regular Coke instead of Diet Coke, and maybe I’ll try some drugs and shove Twinkies in my face all day,” Doughty says. “So much of our culture is designed around staving off death and maintaining law and order to keep death away.”

Most likely, though, the majority of individuals would toggle between being hyper-motivated and nihilistic, opting one week to “sit at home and spray Cheez Whiz on crackers with a 30-pack and watch another Law and Order on Netflix” and the next “to go volunteer at the soup kitchen”, Solomon says. But regardless of where we fall on that spectrum, even the most enlightened among us – especially as we approached our death date – would occasionally become “a quivering ruin.”  

“Changes are stressful,” Feudtner agrees. “Here we’re talking about the biggest change that happens to an individual – from being to no longer being alive.”

Religious disruption

New social rituals and routines might emerge, with death dates perhaps celebrated like birthdays

Practically speaking, no matter where we lived in the world, our day-to-day life would fundamentally change as a result of learning when and how we were due to die.

Many more people might attend therapy, which would develop specialised death-related sub-fields. New social rituals and routines might emerge, with death dates perhaps celebrated like birthdays, but counted down instead of up.

And existing religions would be shaken to the core. Cults could spring up in the spiritual wake left behind. “Do we start worshipping this system that tells us when we’re going to die? Make offerings to the system? Give away our virginal daughters?” Doughty says. “It would absolutely disrupt religious beliefs.”

Relationships would almost certainly be affected as well. Finding someone whose death date was close to one’s own would become a mandatory requirement for many, and dating apps designed to filter for those in one’s cohort would make that task easier. “One of the things that often makes people fear death the most – often more than their own death – is loss of those they love,” Doughty says. “Why would I want to stay with someone who is going to die at 40 if I’m going to die at 89?”

Similarly, if it were possible to determine a death date from a biological sample, some parents may decide to abort fetuses doomed to die young to avoid the pain of losing their child. Others – knowing that they themselves will not survive past a certain age – may opt to not have children at all, or else do the opposite, having as many children as quickly as possible.

We would also have to grapple with new laws and norms. According to Rose Eveleth, creator and producer of the podcast Flash Forward (an episode of which explored a similar hypothetical death date scenario), legislation may be drafted around death date privacy to avoid employer and service-provider discrimination. Public figures, on the other hand, may be compelled to share their dates before running for office (or may cause a furore by refusing to do so). “If a presidential candidate is going to die three days into the presidency, that matters,” Eveleth points out.

And even if not legally required, some individuals may choose to get their death dates tattooed on their arm, or wear them on a military dog tag, so that – in the case of an accident – emergency medical technicians will know whether or not to bother trying to revive them, Eveleth says.

The funeral industry would be profoundly impacted as well: it would cater to the still-living rather than to their bereaved families. “Funeral homes would no longer be able to prey on people in their time of grief to get as much money as possible,” Eveleth says. “It puts power in consumers’ hands in a way that is good.”

On the big day itself, some people might throw carefully curated parties, as those choosing to undergo humane euthanasia are beginning to do in real life. Others, especially those who will die in a manner that could put people in harm’s way, may feel ethically or emotionally compelled to isolate themselves. Still others, Eveleth says, may choose to use their death for a higher artistic or personal purpose, taking part in a play in which everyone actually dies in the end or staging a literal die-in for a cause they believe in. 

Should we come to learn the time and manner of our individual demises, our ways of life would be profoundly changed.

“Human civilisation truly has developed around death and the idea of death,” Doughty says. “I think this would completely undermine our system of life.”

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Correction: Chris Feudtner's affiliation was given incorrectly in a previous version of this story; it is the University of Pennsylvania. We regret the error.

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