Then Proudhon was not free, for he was a "victim of erroneous opinions."This is about Proudhon being racist. In What is Property? he says that people with an erroneous opinion are not free, ergo Proudhon is not free from his Anti-Semitism, not to mention all the other European Chauvinisms.
The capitalist is stealing the value the laborer created... Property is theft.This is about the part in Chapter 3 where Proudhon creates the picture where by calling wages a proper exchange for the value that workers create, the capitalist steals from the workers the values they had added to whatever substance they labour on. Thus while it is not exactly accurate to say that Property is Robbery, the contemporary system of property is indeed theft.
St. Simon coined this maxim!This refers to where Proudhon quotes a version of the popular maxim "to each according to his capacity; to each capacity according to its results!” Of course, this is not the Socialist form of "From each according to their ability; To each according to their need." It caught my eye nonetheless.