This revolutionary pamphlet was written by Lenin in August and September 1917, that is between the two revolutions in Russia. (The February uprising which led to the abdication of the Tsar and the October coup led by the Bolsheviks against the provisional government). Lenin is a theoretician of the Revolution. The book is both theoretical and a ‘manual for the revolution’ at the same time. Lenin draws on Engels and Marx and is at pains to explain that he is offering the “pure” and correct interpretation of Marxism; against various “vulgar” interpretations which are used to justify “opportunism”. Opportunism is Lenin’s word for those who believed in parliamentary road to socialism. In this there is a certain element of religious fanaticism; only we (the Bolsheviks) are the true carriers of the faith. Of course; for Lenin, Marxism was not a faith but a theory which was based on concrete analysis of historical events which had been carried out by Marx with “the accuracy of observation characterising the natural sciences”.