I have essentially reduced the discourses of the Buddha down to the conditioned and unconditioned where there is only a spiritual difference between the two. This spiritual difference occurs after one awakens to the unconditioned. It is easy to see that lots of Buddhist terms fall under the heading of conditioned. Others fall under the unconditioned. The dhyana praxis, for example, is basically conditioned but it can certainly lead us to where no trace whatsoever of conditioned dhammas is witnessed. It took me a while to see this simplicity (it is easy to get immersed in jargon unable to see the forest for the trees). But this simple understanding comes with a warning. Gnosis/seeing is required. There is an actual seeing of the unconditioned (remember the Buddha fell into the category of seer such as ṛṣi, śramaṇa, muni -- the monk stuff came afterwards and is not without its problems).

Now you might ask where does the attā/ātman stuff come in? First, it is a term that is prior to Buddhism which didn't have anything to do with a self, individual, personhood, etc. In modern Buddhist translations it enters in through lowly doors as a pronoun ("self"). It is not really a pronoun. From Yasca's Nirukta we learn that atman is the animative principle. Bodhidharma captured this meaning when he said that people don't "understand the movement of their own hands and feet." As you can see, the Indian mind was quite advanced. What animates this mortal coil of ours—not the skandha coil itself—is the prize. It's the recondite dharma the Buddha-to-be discovered that made him the awakened one/muni. One more thought. Today we are immersed in the darkness of materialism (somewhat like Ajita Kesakambali's beliefs). It is a barrier, so that our very self cannot realize the unconditioned. As a result, we are totally trapped in the conditioned. That ain't good.