“Thus, as [Karl] Kautsky wrote in 1919, there was growing up amid despotic conditions a new class of bureaucratic German exploiters, no better than the Tsarist chinovniks; and the workers’ future struggle against tyranny would be even more desperate than under traditional capitalism, when they could exploit divergences of interest between capital and the state bureaucracy, whereas in Bolshevik Russia these two had coalesced into one. This kind of regimented socialism could only maintain itself by denying its own principles, which it was most likely to do, given the Bolsheviks’ notorious opportunism and the ease with which they changed their tune from one day to the next. The most probable result would be a kind of Thermidor reaction which the Russian workers would welcome as a liberation, like the French in 1794. The original sin of Bolshevism lay in the suppression of democracy, abolition of elections, and denial of the freedom of speech and assembly, and in the belief that socialism could be based on a minority despotism imposed by force, which by its own logic was bound to intensify the rule of terror. If the Leninists were able to keep their "Tartar socialism" going long enough, it would infallibly result in the bureaucratization and militarization of society and finally in the autocratic rule of a single individual.”

Workers Councils (1947), Section 2.5

Workers Councils (1947), Section 2.5

Speech (12 September 1973) http://www.cuba.cu/gobierno/discursos/1973/esp/f120973e.html

Source: A Life in Our Times

"The Union of Soviet Socialist Republics is a Capitalist Society" (1941), in Russia: From Proletarian Revolution to State-Capitalist Counter-Revolution (2017), p. 210

2.1, "The Eve of The Revolution", Essential Works of Lenin (1966)
The State and Revolution (1917)

Le capitalisme, c'est l'exploitation de l'homme par l'homme. Le communisme, c'est le contraire !
[Coluche, Les syndicats et le délégué, Coluche : l’intégrale, 3, Carrère, 1989]
Compare Len Deighton, Funeral in Berlin (1964): "Capitalism is the exploitation of man by man. Yes? Well socialism is exactly the reverse."

Source: Property and Freedom (1999), p. 220

Preface to the Third Edition (August 1942)
The Mass Psychology of Fascism (1933)
Context: In the strictly Marxist sense, there is not even in Soviet Russia a state socialism but a state capitalism. According to Marx, the social condition "capitalism" does not consist in the existence of individual capitalists, but in the existence of the specific "capitalist mode of production", that is, in the production of exchange values instead of use values, in wage work of the masses and in the production of surplus value, which is appropriated by the state or the private owners, and not by the society of working people. In this strictly Marxist sense, the capitalistic system continues to exist in Russia. And it will continue to exist as long as the masses of people continue to lack responsibility and to crave authority.