How can Shia claim to have acquired knowledge from Imams if there are many fabricated hadiths in the chain of narration between Imams and the authors of Usul-e-Arba'a? Or are all these chains of narration considered authentic?
Same question should be put for Sunni books of Hadeeth. Thousands of narration were been fabricated by Sunni narrators for different reasons, so how Sunni Ulama identify the authentic? Our Shia scholars do thorough research on every narration and all its narrators. We don't accept but the narration which is according to Quran and authentic Hadeeth and which has been narrated by authentic narrators one after another. Our main books of Hadeeth have much more authentic Hadeeths that what our Sunni brothers have in their books of Hadeeth.
Wassalam.