"The pamphlet One Step Forward, Two Steps Back was published in Geneva in the summer of 1904. It reviews the first stage of the split between the Mensheviks and the Bolsheviks, which began at the Second Congress (August 1903). I have cut this pamphlet down by half, since-minor details of the organisational struggle, especially points concerning the personal composition of the Party centres, cannot possibly be of any interest to the present-day reader and, in fact, are best forgotten. But what is important, I think, is the analysis of the controversy over tactical and other conceptions at the Second Congress, and the polemic with the Mensheviks on matters of organisation. Both are essential for an understanding of Menshevism and Bolshevism as trends which have left their mark upon all the activities of the workers’ party in our revolution. (...).
The last pamphlet included in this collection, Two Tactics of Social-Democracy in the Democratic Revolution, appeared in Geneva in the summer of 1905. It is a systematic statement of the fundamental tactical differences with the Mensheviks. (...) In casting a retrospective glance at the struggle of the two trends in Russian Marxism and Social-Democracy during the last twelve years (1895-1907), one cannot avoid the conclusion that “legal Marxism”, “Economism”, and “Menshevism” are diverse forms of one and the, same historical tendency. (....) Menshevism is not only a literary trend, not only a tendency in Social-Democratic activity, but a close-knit faction, which during the first period of the Russian revolution (1905-07) pursued its own distinct policy—a policy which in practice subordinated the proletariat to bourgeois liberalism.
In all capitalist countries the proletariat is inevitably connected by a thousand transitional links with its neighbour on the right, the petty bourgeoisie. In all workers’ parties there inevitably emerges a more or less clearly delineated Right wing which, in its views, tactics, and organisational “line”, reflects the opportunist tendencies of the petty bourgeoisie. In such a petty-bourgeois country as Russia, in the era of bourgeois revolution, in the formative period of the young Social-Democratic Labour Party, these tendencies were bound to manifest themselves much more sharply, definitely, and clearly than anywhere else in Europe. Familiarity with the various forms in which this tendency is displayed in the Russian Social-Democratic movement in different periods of its development is necessary in order to strengthen revolutionary Marxism. and steel the Russian working class in its struggle for emancipation".
(Lenin, Preface to the Collection Twelve Years, 1907, www.marxist.org, underlined by us).
"The scission between the Bolsheviks and the Mensheviks within the RSDLP in general, and their bitter struggle at the London Congress in particular, raise in the bourgeois press nasty sniggers which became common. Nobody thinks about looking for the reason of the disagreements, for analysing the two tendencies, for informing the public who read about the history of the scission and about all which characterizes the difference between the Bolsheviks and the Mensheviks (...). There can't be any mass party, any class party, if we don't make clear the basic shades, if there is no open struggle between the different tendencies, if we don't inform the masses about the line which such militant or such party organization follows. (...) We've succeeded that the conceptions of our two tendencies appear clearly to everybody's eyes with honesty, clarity and precision."
(Lenin, And the judges, who are they ?, November 5th, 1907, translated from french by us, only underlined by us).
Bulletin 27 (english version) of the Internal Fraction of the International Communist Current