Nirvāṇa is neither cause nor effect. It is beyond cause and effect. Truth is not a result nor an effect. It is not produced like a mystic, spiritual, mental state, such as dhyāna or samādhi. TRUTH IS. NIRVĀNA IS. The only thing you can do is to see it, to realize it. There is a path leading to the realization of Nirvāṇa. But Nirvāṇa is not the result of this path.
