The culmination of Fromm's social & political philosophy was his book The Sane Society, published in 1955, which argued in favor of humanistic & democratic socialism. Building primarily upon the early works of Karl Marx, Fromm sought to reemphasise the ideal of freedom, missing from most Soviet Marxism, & more frequently found in the writings of libertarian socialists & liberal theoreticians. Fromm's brand of socialism rejected both Western capitalism & Soviet communism, which he saw as dehumanizing & that resulted in a virtually universal modern phenomenon of alienation. He became one of the founders of socialist humanism, promoting the early writings of Marx & his humanist messages to the USA & Western European publics.
In the early 1960s, Fromm published two books dealing with Marxist thoughts (Marx's Concept of Man & Beyond the Chains of Illusion: My Encounter with Marx & Freud). In 1965, working to stimulate the Western & Eastern cooperation between Marxist humanists, Fromm published a series of articles entitled Socialist Humanism: An International Symposium. In 1966, the American Humanist Association named him Humanist of the Year.