In 1956–57 he was chief editor of Życie Gospodarcze ('The Economic Life') weekly, fired for the allegedly revisionist views he espoused (he wanted to reform the overly centralized state socialist system).
[2][5] An active participant of the democratic opposition's leftist current from the 1960s, in the 1970s he was among the signatories of several appeals presented to the communist authorities in defense of repressed activists and he worked with the pioneering Workers' Defence Committee (KOR) human rights group.
In his writings Kowalik used the ideas developed in the 1920s and 1930s by Oskar Lange and other Polish Marxists, who were critical of the socialist (at that time Soviet) industrial organization.
Kowalik was and remained a supporter of the social-democratic economic model and he opposed the prevalent in the 1980s and 1990s neoliberal views that promoted an unbridled free market.
He authored or co-authored numerous books, including Rosa Luxemburg: Theory of Accumulation and Imperialism (1971, 2014 English translation) and From Solidarity to Sellout: The Restoration of Capitalism in Poland (2011).
[7] Kowalik was disappointed by the neglect of the economic legacy of Rosa Luxemburg, Michał Kalecki and Oskar Lange, which he considered applicable to Poland's new reality.
After 1968, Kowalik and Kalecki in a joint paper entitled "Observations on the Crucial Reform" revisited the issues of the Keynesian Revolution from the point of view of the Marxist discussions that preceded it.
[1] From the 1950s, Kowalik was critical of the ways in which state socialist economy was implemented in Poland and worked on its reform, until he was removed from the position of chief editor of the official economic periodical.