The גמרא does give rules to how to decide a law. The trouble is these rules often conflict. Going by the majority is one rule in rare places.

The גמרא does give rules to how to decide a law. The trouble is these rules often conflict. Going by the majority is one rule in rare places.

I have mentioned some of these rules before in other essays. For example the list of sages of the משנה has an order. רבי יוסי comes first then רבי יהודה etc. A משנה with no name סתם משנה is considered the law. The trouble is often this conflicts. For example money in a doubt חולקים is  of the סתם משנה  with no name. Therefore it should be the law. But in a ברייתא it is said in the name of סומכוס against the חכמים so it is not the law except in one case where the רמב''ם brings in  a certain case.

Therefore it is best to have a session in the טור בית יוסף get a good idea in each place how the law is decided. 


The main thing is not to ask anyone's opinion but to do the learning yourself so you know what the Torah requires of you. Or to go to a legitimate Litvak yeshiva and ask the Rosh Yeshiva