The study of the origins, development and criticism of Hadith literature, as we have it today, is essential in determining the extensive source of information about the history of pre-Islamic Arabic, early Islam, and the development of Arabic literature and Islamic law, as well as serving as a source of legislation for the Muslim world.
'Introduction to Hadith' provides a detailed picture of the Hadith of Science or Shia Islam. The book starts with the core of the subject, by outlining the different classifications of Hadith and their process in verification, before dwelling into each in detail and exposing their uncertainties and limitations. The book presents multiple scholarly opinions, which demonstrates that the science is not unanimously agreed on among the scholars. It provides numerous sources and references for further research as well.
This book demonstrates the significant thought and attention paid to preserving Hadiths. The verification process of Sahih Hadiths is the best you can get when tracking information back in history. Unfortunately, it seems that while the categories are well defined, scholars take contradicting approaches to its implementation.
Hadiths that are 'weak', can still be implemented if they are renown. Hadiths that are sahih, can be rejected if they are rare or contradict with a renown weak hadith. Furthermore, a 'weak' hadith can become acceptable if its presence in society is seen as beneficial or self-evident. Lastly, even a rejected weak hadith can still be acted upon by labeling their authority as "recommended" or "not recommended". It is these facts that causes me great concern, and makes me believe the religion is based on a "pick and choose what you like" nature. It seems to be a contradiction to the nature of the science to ignore it's own classification in implementation.
From what I understand, it seems best to rely only on sahih/acceptable/dependenable Hadiths and ignore the rest. A 'weak' hadith becoming renown is an irrational concept. It's as though stating that a false statement becomes true if enough people support it. Furthermore, if a hadith is sahih, it is irrational for anyone to oppose it, despite how rare or odd it may be. It is important to follow the Science closely. It seems that the next steps from here are to learn Arabic and investigate into the hadiths for each legal ruling separately. One cannot simply trust any legal ruling without knowing the authenticity of the hadiths supporting it!