It was nearly 11pm on a recent Friday, after dinner with a friend, and we were waiting at a crowded taxi stand at the Esplanade, right after a performance had ended.
My friend decided to UberPool - share a ride and the cost with other people going in the same direction - her way home.
As we were waiting, she said: "Time is money."
I bristled slightly inside. Sure, I thought, that might be so if you were rushing to sign a multimillion- dollar deal to sell your company instead of just going home.
Then I recalled a New York Times article in September by University of California, Los Angeles professors on the difference between those who choose time over money and vice versa.
They had asked more than 4,000 Americans to choose between more time and more money, and to report their level of happiness and life satisfaction.
The piece got me thinking again about what I was saving - and what for. As a compulsive saver yet to kick the "habit", money has often come before time for me. For a long time, I've saved every cent possible, even if it meant taking extra time.
My first choice of transport is always the bus or train, never a taxi. For starters, I get motion sickness in the back seat of a taxi driven by someone clearly aspiring to become the next Lewis Hamilton.
And there is also the possibility of forking out more than $10 - not forgetting ERP (electronic road pricing) charges.
As a teenager with all the time in the world but not money, I could "afford" a 40-minute trip by bus or train anywhere for under $2.50, over a 20-minute cab ride.
But surely, as a salary-earner now, I could - like nearly everyone I know - afford $15 for a 15-minute taxi ride instead of taking a 45-minute public transport trip.
Still it is not just one cab ride. I have observed how friends and acquaintances, after getting a taste of the convenience, squander a lot of their money taking taxis everywhere they go.
Sometimes, I see someone posting on Facebook, vowing to be more prudent for the rest of the month, after overspending and no longer being able to take a cab. But soon enough, I notice, they will revert to the convenience of cabs.
I can be pretty determined, and even stubborn, not to let my money go to "waste".
I often hop on public transport, just before the services end about midnight, to meet friends for drinks - even in six-inch heels.
I used to be slightly obsessed over how much it costs to get to work - a 30-minute journey with two bus rides costs 78 cents, while a 20-minute train ride costs 98 cents. I get a kick out of saving 20 cents each time I choose the bus.
It used to be a competition with myself to see if I could keep monthly transport costs under $100. Still, in recent months, I've reconsidered the merits of choosing time over money.
I can book a cab and get to a destination in under 20 minutes, instead of setting aside at least 45 minutes - thus eliminating the stress of waiting and travelling.
On another front, I can choose not to queue an hour for the cheapest tempura donburi in town, no matter how delicious it is. The hype dies after a while, anyway.
Was choosing money the wrong choice in the first place?
The professors did not assert that having more of either resource is better or worse for happiness.
But their research found that the value individuals place on time and money relative to the other can be predictive of happiness. In short, those who value time tend to focus on some of the intangibles in life.
The professors wrote: "Unlike those who chose money, who were more likely to be fixated on not having enough, people who chose time focused more on how they would spend it, planning to 'spend' on wants rather than needs (for example, cultivating a hobby versus completing chores at home) and on other people rather than themselves - two expenditures that have previously been linked to elevated levels of happiness."
Being fixated on not having enough certainly sounds like what a compulsive saver does, which does not bode well for investing.
British writer Oliver Burkeman responded to the research, noting: "The crucial finding here is that it's not having more time that makes you happier, but valuing it more."
I was reminded again of how I should value my time by investing in myself and things that really matter, such as health and relationships.
One young investor I have interviewed spends an hour every day after work on researching US stocks before the market opens, while another pores over the news at 6am before work.
But as the New York Times article noted, as we pursue happiness, big and small decisions "constantly force us to pit time against money". Sometimes it's not a choice at all: We must earn that extra pay to make ends meet.
Not everyone may be aware of the importance of weighing money against time. After all, we've grown up in better times with better job prospects, so scrimping and saving is perhaps less fashionable. But I still make do with what I have.
As another friend said, she also chooses the bus or train as her parents have taught her the importance of prudence and time management. To rely on public transport requires good time management, otherwise you end up running late.
In being prudent, we learn about discipline and these are values equally applicable to investing.
A long bus or train ride is also a great time to read or to mull over things, time denied you on a 10-minute cab trip.
And sometimes, in other areas of life, you can achieve a win-win outcome by looking to save money - and gaining time as well.
After the TV in my room broke down earlier this year, I decided not to replace it and got rid of the cable box, an extra $12 a month. I don't watch shows on my laptop either.
I was inspired to do this after a friend said she had returned to reading after work. Binge-watching season after season became mind-numbing and she was no longer the voracious reader she once was.
So I've finally set up my Kindle and hope to finish a half-read One Up Wall Street by renowned fund manager Peter Lynch - but maybe after just one episode of Modern Family on the living-room telly.