The period of national mourning for Mr Lee Kuan Yew will remain vivid in the memory of Singaporeans for many years to come.
For seven days, Singaporeans experienced what I called "nationally shared emotions".
It was a collective grief, accompanied by a deep sense of gratitude to a great man who devoted his adult life to building a city-state that Singaporeans can be proud to call home.
As a behavioural scientist, I was constantly asked over the last two weeks to explain the psychology underlying Singaporeans' public display of emotions.
Singaporeans are now returning to the normalcy of their daily lives. It is time to take stock of Singaporeans' recent collective experiences. And it would be irresponsible to not address the question of a post-Lee Kuan Yew Singapore.
Personal experiences, shared beliefs
MANY Singaporeans grew up with Mr Lee as their iconic leader.
They heard his hard-hitting speeches and experienced his commanding presence even if it was only through watching the television. They have shared beliefs that he was the primary person responsible for transforming Singapore.
But why are younger people - who have not known Mr Lee as their prime minister - also intensively moved?
It is true that they learnt in school that he is the founding father of modern Singapore. But they have also heard about the real experiences of older people or others who know about Mr Lee. And they grew up listening to stories about the rare combination of leadership abilities and values embodied in the man.
In other words, Mr Lee has been Singapore's national leader, who has been revered or talked about among Singaporeans for over 50 years. His influence and impact on Singapore and the lives of Singaporeans has been long and lasting.
And when Singaporeans look at their country, many are likely to agree that, overall, the positives outweigh the negatives.
Psychology of public reactions
DID Singaporeans simply feel obliged to acknowledge that Mr Lee was primarily responsible for the country's improved material conditions? Research on psychological commitment has shown that people can be motivated to do something when there is a sense of obligation.
By itself, commitment based on obligation - as in feeling duty-bound to do something - can explain behaviours reflecting determination and perseverance, such as queueing for many hours to pay last respects to Mr Lee. But it cannot explain the visible grief and public display of emotions.
Complaints of inconvenience, which should occur to some degree if people feel that they have to, even when they do not want to, were conspicuously absent.
Moreover, volunteering and looking out for each other were in abundance. To understand public reactions, we need to go beyond commitment based on obligation to include commitment based on emotion. Emotional commitment is about motivation based on "want to".
When people are emotionally committed, they experience a strong feeling of attachment and sense of belonging. They feel like "part of the family". Studies have shown that emotional commitment is often accompanied by a display of emotions. It also leads to "citizenship" behaviours, such as putting up with inconveniences, pro-social behaviours, taking initiatives to improve a situation, and volunteering.
But given Mr Lee's strict enforcement of obedience to authority at the expense of personal freedom, or an authoritarian approach, can we still say that people are rooted to him through emotional commitment?
In fact, there is no inconsistency. It turns out that emotional commitment can be developed over time through positive personal experiences and beliefs based on perceptions of principled treatment.
First, Singaporeans have personally enjoyed many positives in their life experiences that are attributable to Mr Lee's efforts and decisions. For example, in addition to living in a vibrant metropolis, Singaporeans enjoy a safe and secure country and a harmonious society that emphasises multiracialism.
Despite the usual complaints of stress and strain, Singaporeans have personally experienced a place that is highly liveable, for themselves and their family.
Second, in addition to being a pragmatic leader, Mr Lee has been widely perceived as a man of principle.
While there may not be a consensus on the desirability of all his principles, many that he zealously safeguard have benefited Singaporeans though the building of a fair and just society.
Singaporeans from all social backgrounds have been able to excel and be rewarded under a meritocratic system based on performance rather than one's connections.
People have also experienced fairness and justice from a government with zero tolerance for corruption. And many would describe Singapore as a land of opportunity, where self-reliance can lead to achievements of goals.
Mr Lee is seen as a man who practised what he preached, said what he meant, and meant what he said.
So, beyond his intellect, there was a deep respect and trust for Mr Lee's character. Note that this is not about his personality or rationale for specific policies. Singaporeans may disagree strongly with some policies advocated by Mr Lee or dislike some of his personality traits. But they appreciate the values that he painstakingly cultivated, and the principles that he unwaveringly upheld for Singapore.
Singaporeans' shared values include integrity, fairness and social harmony, and guiding principles such as the rule of law, accountability and people-centricity. For over 50 years, Mr Lee translated these values and principles into Singapore's collective narratives and convictions. And so, today, Singaporeans hold strongly to their beliefs in meritocracy, multiracialism, incorruptibility and self-reliance.
For Singaporeans, Mr Lee's death activated the realisation that the generally good life that they and their children have been enjoying did not come easily. Neither did it come automatically. It came about because of Mr Lee and the team of pioneers he led.
The recounting of past events and Mr Lee's past speeches in the media played a role in this mental activation.
But it was not the primary reason for the public's reactions. People could have responded the way they did only if they have existing strong beliefs, trust and respect for Mr Lee.
And real experiences of positive well-being living in Singapore. These beliefs and experiences have, over time, developed into a commitment that is based on both obligation and emotion.
It is noteworthy, though, that none of the above tells us anything directly about whether Singaporeans are happy or unhappy with the government of the day or prevailing policies.
THE national mourning has also turned out to be a period of reflection. It is likely that Mr Lee will remain an inspiration for many Singaporeans moving forward.
But how do we imagine a Singapore without Mr Lee Kuan Yew?
There are good reasons to be confident that a post-Lee Kuan Yew Singapore will continue to thrive. Precisely because of what Mr Lee has done in building up Singapore and putting it on the map, the world now knows of the Singapore brand - Singapore is a choice place to invest in and partner with.
And this is more than just its strategic location, excellent infrastructure and global connectivity. Backed by its solid record - including the past two decades when Mr Lee was no longer in charge - it is a nation of trustworthy people who can and will deliver what is promised.
In my view, this is Mr Lee's greatest legacy. He has put in place institutions and values that ensure Singapore will continue to survive without depending on any one individual. Singaporeans can be optimistic about the future of Singapore without Mr Lee.
But Singapore's continued success is not a given or guaranteed. The country needs capable and trustworthy leaders who are citizen-centric with a global outlook. Leaders who ensure that the fundamentals of economics and foreign relations are well taken care of.
The country also needs communities who will speak up and step up to address those issues that the Government cannot tackle alone, or those that are better resolved without government intervention. This builds social capital.
And the country needs individual citizens who would uphold shared values and guiding principles.
This should translate into how people think, feel and act. But it also includes the conscious efforts to transmit values and principles to the next generation.
Singapore has the foundations for us to be confident that we can make things happen. As individuals, there is hope to achieve our goals and aspirations. Singaporeans can be optimistic about the progress and future of our society.
And when we recover from adversity and adapt to changes, we become more resilient, individually and nationally.
This psychological capital, together with economic and social capital, will see us through.
The writer is director of the Behavioural Sciences Institute, Lee Kuan Yew Fellow and Professor of Psychology at the Singapore Management University.