I am not saying my previous blog entry is a very complete answer for the Ran. Rav Shach wants to say that there is a way to explain the apparent ] problem in the words of the Ran. [Rabbainu Nisim]. On one hand that "This is forbidden " is forbidden because of an extension of "this is forbidden like a sacrifice" And that does seem impossible because of circular reasoning. "This is forbidden" because of extension [you add the words this is forbidden like a sacrifice. And yet "This is forbidden like a sacrifice" is forbidden because it is part of the law of neder which is simply "This is forbidden"
The answer of רב שך to explain the ר''ן would be to separate the law of extension from the main law. But if this can fit in the ר''ן seems doubtful. {Whether this could fit in the ר''ן or even the רמב''ם does not really seem to work.] However I have reached a state of "fallen mind" and am not really able to spend time learning.--though I should because of the command of the Torah.. Still I mull over this difficulty in the Ran and Rav Shach-hoping for some answer.
--------------------------------------------------------------------------------I am not saying my previous blog entry is a very complete answer for the ר''ן. The answer of רה שך is to say that there is a way to explain the apparent ] problem in the words of the ר''ן. On one hand that "This is forbidden " is forbidden because of an extension of "this is forbidden like a קרבן". And that does seem impossible because of circular reasoning. "This is forbidden" because of extension. [You add the words "this is forbidden like a קרבן." And yet,"This is forbidden like a קרבן" is forbidden because it is part of the law of נדרים which is simply "This is forbidden"ץ