Fukuda was reunited with his family in February 1946. They settled at
Ōiso in Kanagawa Prefecture. With the war over, Fukuda began a new career as a "post-war critic", uniquely uncoloured by the ideologies of
militarism or
Marxism. At the invitation of Ikutarō Shimizu, Fukuda joined the (二十世紀研究所,
nijusseiki kenkyūjo) in 1946. A group of public intellectuals devoted to the promotion of the study of the social sciences and philosophy that was founded that year, its primary activity was the holding of a series of public lectures. Other members included political scientist
Masao Maruyama, economist and jurist
Takeyoshi Kawashima. In the post-defeat debate over responsibility for the
Second World War, Fukuda rejected Masao Maruyama's prominent theory that the Japanese people's inability to resist authoritarianism was caused by their lack of a "modern ego" independent of the
kokutai, or because of the lack of an ideological framework to deconstruct imperialism. Maruyama argued that, in pre-war Japan, the
kokutai had a psychological or magical control over the Japanese people. By contrast, Fukuda argued that the Japanese people lacked the physical means to resist the violence of the state. He believed that humanity was flawed, essentially rooted in the physical
egoism, and that no psychological means could be used to defeat brute force, saying: "It is impossible to expect ordinary people to be heroes; I do not have the courage to face that sort of state authority and continue a fruitless existence." Whereas leftist thinkers such as believed that democratisation would require the Japanese people to overcome physical egoism and become "modern" individuals with strong ideals, Fukuda believed that egoism was a critical element of humanity that had to be balanced with the psyche. He issued a defence of the Japanese people, whom he said held a point of view that was "Japanese", not "pre-modern" or "backward" as asserted by Maruyama. Fukuda expressed hope for a revolution to bring about the democratisation of Japan, but he believed that this should originate from the people, not the intelligentsia. He was particularly critical of the tendency for progressive intellectuals to use "
self-criticism" to justify their superiority to the masses, arguing that practising such criticism was not a licence to criticise others, and did not absolve them of responsibility for their failure to resist the pre-war state. Fukuda posited that the intellectual class were just as complicit in this failure as the common people and the state, an unprecedented argument at the time. Fukuda's resistance to the idea that the common people needed to break free from egoism to become truly democratic also appeared in his writings on
proletarian literature, which he said only served to "praise intellectuals who sacrifice themselves in the name of the liberation of the workers" in a form of what he called "puritan idealism". When Ken Hirano invited Fukuda join the '''' literary magazine, his participation was blocked by , who objected to Fukuda's criticism of proletarian literature in a February 1947
Shinchō article called . In his defence of the egoism of the common man, Fukuda drew particular ire from communists, such as
Kenji Miyamoto, who referred to him as a "
petty bourgeois critic", and also from other critics such as
Shūichi Katō who named him a "petty bourgeois reactionary". During the 1946–1947 , a discourse between leftist literary critics associated with the magazines
Kindai Bungaku and
Shin Nihon Bungaku about the role of literature in relation to politics, Fukuda argued for a clear dividing line between the two. In , which was published in March 1947, and known as one of Fukuda's most significant works, he used the biblical
Parable of the Lost Sheep to make his argument. Fukuda posits that each human possesses both collective (the ninety-nine sheep) and individual (the one lost sheep) egos. Politics, Fukuda says, serve the collective ego, while literature serves to save the individual. He lamented that "whether from the right or the left, the current tendency is to destroy the individual in the name of society". Literature, Fukuda said, should not serve politics nor become a means to effect a political end. Instead, Fukuda argued, the inherent contradiction between the human desires to both belong to a group and be an individual should be accepted, allowing for both politics and literature to serve their own, independent roles. Fukuda wrote the first published literary criticism of
Osamu Dazai in 1948, which appeared in the
Gunzo magazine. He was a founding member of the '''', a literary circle formed during the same year, which included Ken'ichi Yoshida,
Mitsuo Nakamura,
Shōhei Ōoka, and
Yukio Mishima. Fukuda's released the
metatheatrical play in September 1948. In 1949, Fukuda joined the Albion Club, a group devoted to the study of British culture founded the same year. He contributed a criticism of
David Garnett to the first issue of the group's magazine,
Albion. He also published a book, , which rejected Japanese modernisation as "false" and reproducing the west's mistakes. In the work, he praised Garnett for his avoidance of what he called the modern tendency toward "excessive individualism". In March 1949, he published a novel, . The novel is centred upon the life of David Jones, a fictional
Hamlet actor and director at the
Old Vic in London during the Second World War, who later ends up playing
Horatio. In the novel, Fukuda, who had yet to visit Britain, constructed the London theatrical scene of his imagination, and touches on the theme of humanity's struggle to act against the madness of war. ==Dramatic work and trip to American and Europe==