Lee Kuan Yews's memoirs, which point out that the years of the Japanese occupation of Singapore played a major role in his conceptions of human nature and his political philosophy, relate several first-hand experiences of the conqueror's brutality. As he explains, his own first "encounter with a Japanese soldier" occurred when he tried to cross a bridge to visit his mother's younger sister
As I approached the bridge, I saw a sentry pacing up and down it. Nearby was a group of four or five Japanese soldiers sitting around, probably the other members of his detail. I was sporting a broad-brimmed hat of the kind worn by Australian soldiers, many of which had been discarded in the days before the surrender. I had picked one up, thinking it would be useful during the hard times ahead to protect me from the sun. . . . One soldier barked "Kore, kore!" and beckoned to me. When I reached him, he thrust the bayonet on his rifle through the brim of my hat, knocking it off, slapped me roundly, and motioned me to kneel. He then shoved his right boot against my chest and sent me sprawling on the road. As I got up, he signalled that I was to go back the way I had come. I had got off lightly. Many others who did not know the new rules of etiquette and did not bow to Japanese sentries at crossroads or bridges were made to kneel for hours in the sun, holding a heavy boulder over their heads until their arms gave way. [53-54]
Immediately after relating the incident in which he had gotten off "lightly," Lee tells that when a rickshaw puller pleaded for more money from a Japanese soldier, he "took the man's arm, put it over his right shoulder, and flung him up into the air with a judo throw. The rickshaw puller fell flat on his face. After a while, he picked himself up and staggered off between the shafts of his rickshaw. I was shocked at the heartlessness" (54). The next day, he explains, he received a lesson that explained in part how Japanese soldiers could treat civilians with such barbarity. When an officer's car drove past a sentry at the same bridge at which the young Lee had been slapped and kicked,
The sentry was slow in coming to attention to salute. The car had gone past, but its driver braked and reversed. An officer got out, walked up to the sentry and gave him three hefty slaps. Taking his right arm, he put it over his shoulder and, with the same judo throw I had seen used on the rickshaw puller, flung the soldier in the air. The sentry fell flat on his face, just as the rickshaw puller had done. This time I was less shocked. I had begun to understand that brutalisation was part of the Japanese military system, inculcated through regular beatings for minor infringements. 
Admitting that Japanese proved themselves fearsome fighters who in defeat handled themselves with admirable pride, Lee nonetheless concludes that their army (which had massacred at least fifty thousand unarmed Singaporeans) was guilty of unparalleled savagery: "After seeing them at close quarters, I was sure that for sheer fighting spirit, they were among the world's finest. But they also showed a meanness and viciousness towards their enemies equal to the Huns'. Genghis Khan and his hordes could not have been more merciless."
All these discussions of Japanese savagery occur, of course, in the political memoirs of a man who was to become the architect of postcolonial Singapore. In other words, they appear not just to testify to the horrors of the occupation and to Lee's luck and ingenuity in having survived it but also to explain what the future prime minister learned, among other things, about how human beings adapt to superior force and the way social structures crumble.
Lee Kuan Yew. The Singapore Story: Memoirs of Lee Kuan Yew. Singapore: Times, 1998.