There are only three doors, that's how. I don't care what tradition you subscribe to, what practice you do, or who you are, there are only three basic ways to enter the attainment of fruition, nirvana, nibbana, or whatever you want to call it. These doors relate directly to profound and direct realization of the three characteristics of impermanence, dissatisfactoriness, and no-self, and you must understand the heck out of these to join the ranks of the awakened ones.
