A clear, still morning rushed past as pilot Richard Champion de Crespigny lifted the nose of the A380 from the runway at Singapore’s Changi Airport. Bound for Sydney, the passengers barely had time to get comfortable when two bangs sounded. The plane began to shudder.

A turbine disk had exploded from one of the engines, breaking into shrapnel that ripped hundreds of holes in the Qantas aircraft. Shock ran through de Crespigny. Then the captain’s decades of training kicked in. “It could have easily gone the wrong way and the aircraft crashed,” he says of the 2010 crisis. Simply following procedure would get the five pilots in the cockpit only so far. It could even risk putting the 469 people on board in greater danger. The crew had to think independently of the systems, and follow de Crespigny’s lead. “There are so many ways to make decisions, and on QF32 we used all of them,” he says.

Making decisions is somewhere between art and science. Flying a plane with engine failure might be one extreme, but we all make life-changing decisions sometimes. A handful of them carry more weight than others: What career will I pursue? Should I stay or leave a relationship? Where should I live? Should I have kids? When do I retire? When we get stuck, emotions, values, plans and consequences roll around like metal balls in a handheld maze, each a balancing act to navigate.

So, is there a good way to make big decisions? When should we rely on intuition? And what is the role of regret?

How do you decide on matters of life and death?

The cockpit shook, alarms blared and large warning lights flashed red. While panic would overwhelm most of us, de Crespigny didn’t hesitate. He stopped the aircraft from climbing, knowing it was high enough to clear any mountains, and overrode the autopilot.

Pilots are taught that the first 30 seconds of a crisis “can be the difference between life and death,” de Crespigny says. “All I did was make sure the aircraft was flying and that we were safe.”

In those critical first few seconds, it’s important to “create time”, he says. “Don’t get drawn into making any rash decisions.” Panic is a subconscious response that pilots train to overcome. “Practising being out of your comfort zone is really good for protecting you from the fear response,” he says.

The plane was momentarily safe but the damage was severe; one engine was destroyed and another three were degraded. All but one of the 22 flight systems had problems, including the brakes and landing gear. The pilots put the plane in a holding pattern while they ran computer checklists that helped them stabilise the damage and prepare for an emergency landing in Singapore.

One theory of how we think, popularised by Nobel prize-winning psychologist Daniel Kahneman – including in his 2011 book Thinking, Fast and Slow – breaks our minds into two systems. The first uses mental shortcuts from prior experience. The other strains over slow, deliberate decisions. De Crespigny needed both to survive this crisis. “When you’re flying an aircraft, the 35 years of flying experience that I had gave me all these basic skills to operate subconsciously,” he says. “It makes decision-making fairly quick – or you’ve at least thought through the processes.”

‘Keep calm, don’t rush, create time, never presume or assume, and face only the danger in front.’

Still, he and his team thought hard before following many of the aircraft’s checklists; they ignored a direction to transfer fuel from one wing to another, for example, given there were holes in the fuel tank. “If we had followed those checklists we probably wouldn’t have gotten back.”

Nearly two hours after the explosion, a “magic silence” came over the flight deck as de Crespigny dropped the plane towards the runway, he recalls in his book QF32. The plane was overweight, too fast and with limited runway length available. A stall warning sounded metres from the ground. The plane used nearly all four kilometres of tarmac to come to a halt. “After we’d stopped, I had a moment of pleasure thinking the crisis was over, but it wasn’t, it was like a bushfire when the wind changes direction,” he tells us.

In fact, the decision-making was only entering another phase. Fuel was pouring out of one wing near the plane’s hot brakes. One of the engines would not shut off. A complex question arose: should they evacuate via emergency slides that would, among other risks, injure the elderly or put passengers in danger of igniting jet fuel if they walked through it? “We decided to keep the passengers on board,” de Crespigny says, believing it was safer to wait for stairs for them to exit, adding, “passengers could have died if forced to evacuate.” “I would say 60 per cent of pilots would say we made the wrong decision not to evacuate,” he says. But he kept returning to his training: “Keep calm, don’t rush, create time, never presume or assume, and face only the danger in front.”

Are there techniques for making big life decisions?

November 11, 1838 was “the day of days!” Charles Darwin wrote in his journal. His excitement wasn’t due to a breakthrough in his theories of evolution – he’d asked his cousin, Emma Wedgwood, to marry him and she’d said yes. It would be a union of four decades; the rest of Darwin’s life. Months earlier, though, he had been weighing marriage against his scientific career.

The most common big decisions people make involve their relationships, family, career, education, finances and home, says University of Technology Sydney associate professor Adrian Camilleri. He has asked 658 people about their biggest decisions, finding these moments were often rare, uncertain, required contemplation, involved personal morals or values, affected multiple people and had long-term consequences. “The more of those elements that are part of a decision, the bigger it is,” he says.

Darwin used a rudimentary tool to ponder marriage. He ruled his page down the centre and scribbled a pros and cons list. The upsides were children, companionship, love and play, all of which were “good for one’s health”. But there were downsides, such as less “conversation of clever men at clubs”, more “expense and anxiety” of children, and “perhaps quarrelling”. The pros had it. Darwin jotted his conclusion at the bottom of the page: “Marry.”

Several experts told us pros and cons lists were useful if the alternative was that you wouldn’t spend time thinking through a decision. In some ways, pros and cons remain state of the art, “because the art hasn’t advanced much,” says Steven Johnson, who researched long-term decision-making in his book Farsighted. “This got more and more scandalous to me as I researched and wrote the book; no one had ever told me how to make a decision.”

Still, a pros and cons list can reduce big decisions into either/or choices too early. Relationship concerns framed as “stay or go” are one example, says Dr Rowan Burckhardt, director of the Sydney Couples Counselling Centre. He finds people who are no longer in love rarely find therapy beneficial. But for others working through conflicts or differences, it can open up options. “You think that you’re facing two roads in front of you: one is separation and one is just putting up with this forever. But in fact, there is a third path – you just don’t even see it.”

Johnson adds another approach: “If you don’t predict well, then you can’t decide well.” Some businesses like to call it a “pre-mortem” – a way of foreseeing nightmare scenarios in advance of a decision. But Johnson thinks of it more as a form of storytelling that can plot positive or surprising outcomes too.

“The other important thing is having a diversity of storytellers,” he says, to offer their perspectives. “People just make better, more farsighted decisions when they make them in heterogeneous groups.” Before making a critical decision about a checklist on QF32, de Crespigny consulted each member of his team from the lowest-ranked pilot up, to make sure he hadn’t overlooked anything. “If you start at the bottom, everyone is going to have their say,” he explains. “You don’t get any groupthink, and you certainly don’t get peer pressure from someone being reticent to speak up.” He suggests using this technique at home, asking the youngest child’s opinion before their siblings.

With any big decision, says Ben Newell, a professor of behavioural science at UNSW, gathering as much information as possible is preferable before drilling down to what you value most. “It sounds like a trite thing to say, but it’s true: if you can get the evidence as much in front of you, that will help you distinguish between the choices,” he says.

‘When you identify your values, it makes it easier for you to make a decision.’

De Crespigny believes he’s “pretty good” at making everyday decisions: “When the wife says, ‘What would you like for dinner?’ I say, ‘What are the options?’ When we pose a question to our children the first thing they say is, ‘What are the options?’ So I’m particularly pleased that it has rubbed off on them.”

Newell then suggests prioritising the most important aspect of the choice. When buying a house, for example, “is your budget the thing that’s driving you, is it being in an area that’s not going to be prone to floods?”

With the options and scenarios on the table, Johnson says, the question becomes about what you value most. “[Perhaps] having kids is much more important than conversations with clever men in clubs; they’re both meaningful, but one is way more important,” he says of Darwin’s choice. De Crespigny stays aware of his personal values when deciding too: “When you identify your values, it makes it easier for you to make a decision.”

There are plenty of decisions de Crespigny has agonised over too. As a family man, he was unable to take as many risks in life as he might have liked. But his piloting career ended unexpectedly because of COVID, and his children have now finished school. So, after refusing for many years to ride the Cresta toboggan run in Switzerland, it was time. “You go headfirst at 80 miles an hour with your head two inches from the ice,” he says. “Your risk appetite changes during life.”

When the moment comes, for obvious reasons, no single approach to a decision can tell you exactly which way to go. But the experts we spoke with said people were generally happier with their decision when they had used a method and spent the time they needed to make it. “Having some kind of structure is the most important thing,” Johnson says.

Can ‘going with your gut’ or ‘sleeping on it’ help?

We’ve all experienced someone not needing to mull over a decision, perhaps believing they “just knew” what to do. They might have raised their hand at an auction because the place had a clawfoot bathtub like their grandmother’s, or married the person of their dreams after just a few romantic dates. How much should we let our subconscious do the deciding?

UNSW professor Joel Pearson, author of the upcoming book The Intuition Toolkit, says intuition – that subconscious response people feel in their body and can act on – is learned from experience, so brings risks when we deploy it in situations we rarely encounter. “Situations where time is limited and all the information is uncertain, ambiguous or limited are probably the most obvious cases to use intuition.”

But don’t rely on your gut if you’re stressed, anxious or angry. “You confuse what caused that emotion with the emotions for a decision,” he says. “Wait until you’ve calmed down and you’re in a clearer state.” Given intuition comes from experience, we should be wary of attempting to use it in a different context than we learned it in, too. “If you become an expert in something in the workplace, that doesn’t mean your intuition will transfer,” Pearson says.

After the flight, de Crespigny shared his phone number with every passenger, telling them to call if they had any difficulties with the aftermath of the ordeal. He didn’t think much before deciding to do that. “I truly wanted to make sure that they were happy when they were home and they weren’t going to be traumatised,” he says. “By accessing my emotional brain and coming up with why I have to do something, I’m not in conflict at all when I have to make decisions.”

What about the role of sleep, dreaming and the unconscious in helping make decisions?In de Crespigny’s experience, for example, dreaming can help him feel less inhibited in his thinking. “When you dream you can be creative and think up solutions you never thought of when you’re awake – it’s really good to take a problem to bed.” When it comes to making a tough decision, though, scientists have difficulty proving that delegating a decision to your subconscious brings benefit, says Newell. He has studied whether people make better decisions while distracted from focusing on a problem compared to people who are focused on making a decision, and found “people that deliberated made just as good, if not better decisions”.

‘I’m thinking about it again, but I’m thinking about it in a different way, and that then leads to a better solution or a better answer.’

Still, there is something to be said for “sleeping on it” or “going for a walk” to let the mind rest rather than wander. As Rachel Searston, a psychology researcher at the University of Adelaide, notes, “decision fatigue is a real thing”. She has observed fingerprint examiners making decisions who say they distinguish between final options better after coming back with fresh eyes the next day. “We can do that in our everyday life too,” she says.

Says Newell: “I stop and then I come back, but when I come back, I’m then engaging in that deliberative thinking again,” he says. “I’m thinking about it again, but I’m thinking about it in a different way, and that then leads to a better solution or a better answer.”

Crime writer Agatha Christie made this deliberative process a lot of fun: in 1966, she said she came up with fresh plots for murder mysteries when she left her desk and had a bath, lining the rim with apple cores and “just sitting there thinking”.

When he was US president, Barack Obama famously wore only grey or blue suits to cut down on trivial decisions. “I don’t want to make decisions about what I’m eating or wearing,” he told Vanity Fair in 2012. “Because I have too many other decisions to make. You need to focus your decision-making energy. You need to routinise yourself.”

How can we approach decisions involving loss or regret?

In the 51 years that Judith Viorst lived in her stately Washington, DC home, she made a habit of walking on the wraparound porch and putting her arms around one of the Ionic columns. “I love this house,” Judith, author of the 1986 bestseller Necessary Losses, would remark to her husband Milton.

But they were reaching their 90s. Milton, a former Middle East correspondent for The New Yorker, was gasping for breath walking the three flights of stairs, and the Victorian-era foundations were themselves showing their age. Then, when the couple were on their way to a medical appointment to check Milton’s balance, he lost his balance and fell on top of her, breaking her pelvis. Even before then, her mobility was waning too. “We started realising, we’re old. No kidding,” Judith says.

Judith, now 92, has given her fair share of thought to loss: “We lose not only through death, but also by leaving and being left, by changing and letting go and moving on,” she wrote in Necessary Losses, which explores the separations and losses that punctuate our lives. But downsizing to a retirement village wasn’t a loss she had foreseen for herself. “It was really like the five stages of grief.”

Her house was a time capsule of raising three children, celebrations in a dining room that sat 23 people, and two studies where she and Milton had done their writing. (Milton, who died in 2022, wrote 10 books, Judith has authored 43.) To stay or go? “It was a monumental decision,” she says.

At life’s big forks in the road, Judith will first acknowledge the losses involved. “You don’t kid yourself or try not to think about it,” she says. “Say, ‘This is something I love, that I’m giving up, or that’s being taken away from me’. You sort of have to face the reality of the loss head on, and then you can start to think about stages of life, passages of time.”

The experience of regret, says Adrian Camilleri at UTS, often strikes people when they haven’t made a decision, or one has been taken out of their hands, and it’s too late to change the outcome. “It’s maybe not that they made the wrong decision, or they would have made a different decision, but it’s the fact that they didn’t go through that process of actively deciding.”

‘I don’t think you go through life brooding over whether you went left instead of right.’

For Judith, it seemed impossible to leave the house: the closets, a basement and an attic were full of furniture, 15,000 books and five decades of belongings. What to do with them all? “All of these were decisions that we had to make,” Judith says. “I don’t think there was anything quite like this since when we decided to get married.”

With help from family and friends, they found four retirement villages they might like and settled on one. “It’s really pretty, filled with sunlight. There were beautiful leaves fluttering in the breeze against all of our windows,” Judith says. “What you’re looking for is something that will make it easier to have made that decision.” Then buyers began to inspect her house. She “hated” them. “Somebody said, ‘I wonder if we can get rid of those columns?’”

The right buyer eventually came along; a family similar to the Viorsts all those years ago when they moved in. Before she left the keys behind, Judith invited friends from her street for a “farewell ceremony” where people told stories and reminisced about the house. And she’s been back as a guest since, touring a renovation that has repaired or replaced all the details she loved. “It is absolutely beautiful; it’s become their house, it’s not my house any more.”

Life in a two-bedroom apartment is certainly different, Judith says, and a retirement village isn’t like the old neighbourhood. “Everybody is old, you’re not going to see a five-year-old learning to ride a bike.” But she has close friends and plenty of time to write. “It is as satisfying as it could be.”

Over her 92 years, what she sees as peoples’ biggest decisions will sound familiar to many of us: who to marry, what career to pursue, whether to have children, and what personal values to uphold. There’s no point making a drama of it, though. “That’s called growing up,” she says. “I think there are losses involved in making choices. But I don’t think you go through life brooding over whether you went left instead of right. I think you make the best of it.”

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