Graciousness might not seem like the most important thing in defining the success of a nation, but it is paramount for Mr Lim Siong Guan, the Institute of Policy Studies' fourth S R Nathan Fellow for the Study of Singapore.

Having served 37 years in the civil service, five of which as its head, Mr Lim said that based on his experience, there are four words to describe what Singapore needs in order to be a successful and sustainable nation state - "gracious society, Smart Nation".

He said: "We are a First World economy, but I don't think we can say that we are a First World society.

"We need to think about how to not just do good for ourselves, but also for future generations.

"We need to think about what kind of society we aspire to be."

He was speaking yesterday at the launch of his book, Can Singapore Fall? Making The Future For Singapore, which is a compilation of three lectures he delivered between September and November last year.

Mr Lim said that while thinking about the lectures, he came to the conclusion that to succeed and avoid "social decay", Singaporeans needed to think about the kind of society they aspired to be.

"You might not agree with me or my conclusions but my real desire is to get Singaporeans talking and debating," he said.

The aim of the lectures and the new book was simply "to get Singaporeans to think", he added.

"It is about thinking why we do things. We might all stand on the left when on the escalators, but are we doing it because we are afraid of being punished, or do we do it because we want to make moving easier for others," Mr Lim said.

He urged Singaporeans to create a gracious society and to build a culture of innovation, excellence and outwardness.

Education Minister Ong Ye Kung, who helped launch the book at the Lee Kuan Yew School of Public Policy, said Mr Lim was his mentor.

"Everywhere I look in public service, Mr Lim has left an indelible mark," Mr Ong said.

Mr Janadas Devan, director of the Institute of Policy Studies, said the lectures by Mr Lim last year had the highest number of attendees among all lectures delivered by S R Nathan Fellows.