Is the World Socialist Movement a credible source?

At the bottom of the question you will find the proper answer given by a member of the SPGB, not even the left wingers know the proper definition of Socialism and capitalism, not even Lenin gave the proper definition of socialism and capitalism, for many Leninist socialism is the workers state and capitalism is private property. The schools of economics will never give the proper definition of capitalism, they have a romantic version, even more peoples with PHD degree they do not know the proper definition of capitalism and socialism The WSM has given properly the definition of both economical conception. We have been defining socialism-communism and capitalism for more than 100 years, therefore, we know what we are talking about, we have written thousands of pages about socialism-communism and capitalism, not from the top of our head, but doing the proper investigation, we do not and article or a pamphlet without doing a prior research. We are one of the most reliable sources, and I use it daily to answer any question and to document my research, it is a like a library and an university on socialism and capitalism