One February day in 1966, Raja sat in his new spartan office in City Hall and settled into his rich world of ideas. He ignored, for the moment, his in-tray piled high with turgid memos: problems with neighbouring countries, proposals for overseas embassies, plans for his trip with the prime minister to Eastern European countries. Also buried somewhere underneath was the SOS list of his threadbare ministry. The space, on the first floor in the west wing of the building, still had an air of work-in-progress about it. There was the acrid whiff of fresh paint and crisis.

Each day brought new conflicts and decisions. But few were more demanding on Raja's creative faculties than the task at hand – distilling the essence of Singapore's ideals and identity into one sentence. The words would form the country's national pledge. He could not know it then, but it would be considered his most enduring legacy to Singapore.

The exercise had begun in response to a request for help from his Cabinet colleague Ong Pang Boon. Like Raja, he was adjusting painfully to Singapore's independence. The KL-born leader had fought alongside Raja and Toh during the Malaysian Malaysia campaign, and had been as devastated as the duo at being forced to accept Separation.

Ong had a gentle disposition, but was as tough as the boots he wore as a volunteer of the newly formed paramilitary defence unit, the People's Defence Force. He had to be. As education minister, he had to root out communist infiltration in Chinese-medium schools and roll out the government's multilingual and multiracial policy. Now, with independence, an important part of his brief was to inculcate national consciousness and patriotism among the half million pupils who made up over a quarter of the country's population.

In his letter headed “Flag Raising Ceremony” dated 2 February 1966, Ong sought Raja's advice on the wording for a students’ pledge of allegiance to the flag. By way of background, the education minister detailed the practical problems of holding school assemblies every day for a flag-raising ceremony. The compromise was, he wrote, to have the pledge recited daily by students in classrooms and at least once a week in a school assembly “wherever possible”. Furnishing two versions drafted by staff, he asked Raja for his comments and for “whatever amendments you wish to suggest”.