It was late morning and I had boarded bus No. 73 for my daily commute to the office. I tapped my ez-link card on the reader and discovered to my surprise that there was not enough money stored in it to cover my fare.
I dug into my wallet, only to find I had neither coins nor $2 notes.
As the bus trundled on, I stumbled along the aisle asking fellow passengers if they could help me break a $10 note. None could.
Just as I was about to give up and pay $10 for the short ride from Serangoon Gardens to Toa Payoh, two people sprang up and offered to pay my fare for me.
One was a woman in her 40s wearing a shade too much makeup and clothes a tad loud and revealing for her age, someone I would usually have disapproved of at first sight.
But there she was, holding out her coin purse and asking me how much I needed. I looked more closely and saw the kindness in her face and eyes.
The other was a bespectacled man in ill-fitting jeans and polo shirt, who dug out a spare ez-link card from his large haversack and asked me to use it.
He also gave me some advice: I should always carry two ez-link cards as he did, so I would not have this problem again.
He was inarticulate but sincere. I gladly accepted both his spare card and advice.
I was reminded of this incident a few weeks ago when I read Dr William Wan's commentary in this newspaper, "It's time to update the kampung spirit", in which he encouraged us to look on our neighbours as "friends in waiting".
Dr Wan, who is the general secretary of the Singapore Kindness Movement, wrote: "As traditional kinship support weakens, and as our population ages, we need to build bonding communities in which people living near one another are able to give and receive help when needed. It must start with a recognition that we are mutually dependent on those who live around us."
To be honest, if I had not run out of money on my ez-link card that morning, I doubt I would have found much in common with my fellow passengers on bus No. 73, much less thought that I would need to depend on any of them for help.
One of the downsides of living in a rich country is that we have far less need to rely on one another. When we can pay for what we need, we no longer have to depend on the kindness of neighbours and strangers.
So the occasions to get to know one another, to establish ties, to discover what we may have in common, are also diminished.
But seeking common ground is precisely what we need to do as differences in incomes, nationality, political and religious beliefs threaten to pull us further apart.
We need to build solidarity - a sense that we are all in this together, playing on the same team as we face the challenges that life throws up; a sense that there is more that binds us than divides us.
And that solidarity is all the more important as Singapore moves towards social policies that will involve greater risk pooling, such as MediShield Life, and more redistribution of the rewards of economic growth.
These policies cannot work as they are intended to if the social paradigm is every man for himself.
Take MediShield Life as an example. It is a universal health-care insurance scheme that, when launched next year, will cover every Singaporean for life.
The premise of this scheme is that none of us knows what illness or calamity might strike us and when.
Instead of going it alone, which would leave those on lower incomes struggling to pay for health care, and many of us at risk of having our savings wiped out by a catastrophic illness, MediShield Life is a way for everyone in society to pool their risks and share the costs of medical care.
It will mean that some people who pay a lot into the scheme, which is compulsory, may end up claiming very little if they remain healthy.
Others may claim more than they put in, especially if they are already old or sickly.
It is a scheme that depends on everyone chipping in, as the Prime Minister said in a Facebook post in March to mark the end of the Budget debate.
Mr Lee Hsien Loong zoomed in on the Government's plans to strengthen social safety nets and described MediShield Life as a key initiative.
"MediShield Life depends on everyone chipping in to share the burden, to take collective responsibility to protect one another," he said, adding: "While MediShield Life gives us peace of mind for our health costs, let's all do our part to stay healthy and avoid getting sick. This is the best way to keep health costs low, live long and live well."
So what would help build the solidarity that this society needs to thrive?
Shared public spaces are a good starting point; parks, hawker centres, and buses and trains are where Singaporeans come face to face with one another.
People also need opportunities to interact, to work and play together, to discover what they can do together that they cannot do alone. The Ministry of Culture, Community and Youth is taking a stab at growing these opportunities through events such as the annual Community Games, but just as important is giving civil society the space it needs to flourish.
Another change that must take place is the removal of social structures that undermine solidarity.
In a chapter in his new book Hard Choices, Mr Donald Low sheds light on some of these structures as he provides an insightful critique of Singapore's meritocracy.
He contrasts meritocratic competition based on absolute performance and that based on relative position.
The first sets up a positive-sum game that adds to society's well-being. One example of this is the Singapore Armed Forces' Individual Physical Proficiency Test.
The second sets up a zero-sum game where everyone tries to outdo each other in the hope of securing the rewards that accrue only to those at the top. An example of this is the way the education system often grades students on a curve, or ranks them, as in the case of the Primary School Leaving Examination and its T-score.
To build solidarity, we need to do away with forms of competition that encourage people to see each other as foes in waiting, rather than as friends.