Laws Given to Moshe, from Sinai
Despite all of the above, there is a rare class of laws that are simply part of the oral transmission of Torah, laws that cannot be found in any verse of the Written Torah. These are called “Laws Given to Moshe, from Sinai.” For example, the Torah never says that certain holy texts must be written in black ink on a prepared animal skin, yet there is a received tradition that this is so.
So in reality, the Torah comprises three varieties of laws:
1. Those that are explicit in the Torah
2. Those that can be derived using the rules of hermeneutics
3. Those given to Moshe, from Sinai
Maimonides points out that whereas two courts can disagree about the application of the laws of hermeneutics, there can be no conflict about that which is explicit in black and white, or that which is a received tradition. So everywhere one finds an argument, it always has to do with the application of the rules of hermeneutics in the most logical fashion.