SINGAPORE - When drinking water, think of its source.

Presidential hopeful Ng Kok Song quoted the Chinese idiom on Thursday to emphasise that a person cannot easily be separated from his past affiliations, in response to potential competitor Tharman Shanmugaratnam’s comments on having independence of mind.

Speaking to the media after a visit to Geylang Serai Market on Thursday, Mr Ng, 75, a former GIC chief investment officer, said: “Our present is related to our past. We cannot easily separate our present from our past.”

“My past is that I was in the public service for 45 years, and Mr Tharman served many years in political leadership,” Mr Ng added. “You draw your own conclusion.”

Mr Tharman, who stepped down from his role as senior minister and resigned from the ruling People’s Action Party (PAP) on July 7, had on Wednesday distinguished between independence from a past affiliation with a political party, and independence of mind and character.

The former PAP central executive committee member had urged the public to judge each candidate on his positive attributes, track record and what role he can play at home and abroad, rather than his past affiliations.

Mr Ng also responded to Mr Tharman’s vision of being a president for a new era. He said one feature of the new era of Singapore’s governance is a balance between the presidency and the Government. “I think the people of Singapore would like to see this balance in this new era: Where the president is above politics, where the president has no political affiliation.”

On Thursday, Mr Ng walked around the market greeting stallholders and market-goers before having mee soto for lunch with his fiancee Sybil Lau. Ms Lau, 45, sits on several boards, including SG Enable, a registered charity for persons with disabilities.

Mr Ng used the occasion to clarify a comment he made in an earlier interview with The Straits Times, where he said he was “running for president because (Mr Tharman) wants it”.

This was in reference to a remark by Mr Tharman when he announced his presidential bid that he would welcome a contest, said Mr Ng.

“I have come forward so that there will be an election, so Singaporeans have a chance to choose the president,” he said. “And I have come forward so that there is a good contest – if I am certified eligible.”

Mr Ng also elaborated on why he picked Chinese President Xi Jinping as one of three people, living or dead, that he would want to have dinner with.

In a quick-fire video interview with ST, Mr Ng had listed the Chinese leader alongside his late wife and his mother.

He said: “Xi Jinping will be perhaps the most important person who will navigate China in the future, and who will affect the future of the world, affect the future of the Singapore economy in terms of whether we have peace, a cold peace, a cold war or a hot war.

“That is why leaders from all over the world go to Beijing to meet President Xi. I would like to meet President Xi as well, to understand his way of thinking and to have an appreciation of his aspirations for China and for the world.”

Responding to queries on his own team of assenters after Mr Tharman, 66, unveiled his proposer, seconder and assenters on Wednesday, Mr Ng said he was forming his team, but he would not announce its composition until he is certified eligible to run.

Mr Ng said: “It is a very high-powered list that Mr Tharman has assembled. But my list of assenters will be also high-powered – high-powered in terms of being heart-powered. Because the people who have come forward to help me by being my assenters, they come from different walks of life.”

It has not been easy to assemble this group as he is the underdog in this race, said Mr Ng.

“Signing up for me, there is no upside, (but) there is some downside,” he said. “The people who have come forward on my list are people of courage.”