That and that alone is the scientific reason for speaking of a new revolution whicharguing purely theoretically taking the question in the abstractcould be accomplished legally if for instance the Constituent Assembly convoked by the bourgeoisie produced a majority opposed to the bourgeoisie if the majority belonged to the parties of the workers and poor peasants

What is the correctly punctuated version of this sentence?
That, and that alone, is the scientific reason for speaking of a new revolution whicharguing purely theoretically, taking the question in the abstractcould be accomplished legally if, for instance, the Constituent Assembly, convoked by the bourgeoisie, produced a majority opposed to the bourgeoisie, if the majority belonged to the parties of the workers and poor peasants.