How do we choose a “Way” to follow? We have to ascertain whether someone is qualified to give us Laws, and then follow them. A child can’t judge by himself which of his parent’s rules are necessary and which aren’t. Trying to assess the words of the Prophets this way leads to endless arguments.
Likewise, a patient does not find a good doctor by seeking the “correct prescription” for his illness. Only a doctor can know that. Instead, we look for the signs of skill and experience which distinguish a good doctor, and put ourselves in his hands.