Almost every religious prophet, mystic guru, spiritual sage, revered master, elevated yogi, or other supposed knower of what lies beyond everyday appearances shares a common denominator:
They were essentially clueless about the human brain with which they made their pronouncements about divine reality.
So they had no idea about how the knower of their purported knowledge works.
I'd realized this before, but the factiness of this fact hadn't really hit me until I started reading Patricia Smith Churchland's "Brain-Wise: Studies in Neurophilosophy."
In the Introduction, Churchland reminds us how neuroscience has only come into its own very recently. By contrast, advances in physics, astronomy, and such were able to be made much earlier.
By the end of the nineteenth century, physics, chemistry, astonomy, geology, and physiology were established, advanced scientific systems. The science of nervous systems, however, was a much slower affair.
...The crux of the problem is that brains are exceedingly difficult to study. Imagine Hippocrates observing a dying gladiator with a sword wound to the head.
...Remember, in 400 B.C. nothing was understood about the nature of the cells that make up the body, let alone the special nature of cells that make up the brain. That cells are the basic building blocks of the body was not really appreciated until the seventeenth century, and neurons were not seen until 1837 when Purkyne, using a microscope, first saw cell bodies in a section of brain tissue.
...Figuring out how neurons do what they do requires very high-level technology. And that, needless to say, depends on an immense scientific infrastructure: cell biology, advanced physics, twentieth-century chemistry, and post-1953 molecular biology.
...Bit by experimental bit, neuroscience is morphing our conception of what we are. The weight of evidence now implies that it is the brain, rather than some nonphysical stuff, that feels, thinks, and decides.
That means there is no soul to fall in love. We do still fall in love, certainly, and passion is as real as it ever was. The difference is that now we understand those important feelings to be events happening in the physical brain.
It means there is no soul to spend its postmortem eternity blissful in Heaven or miserable in Hell. Stranger yet, it means that the introspective inside -- one's own subjectivity -- is itself a brain-dependent way of making sense of neural events.
The ancients did as well as they could with the knowledge they had.
Buddha, Jesus, Muhammad, Taoist sages, Hindu seers -- everybody who sought to understand reality before the advent of neuroscience did so with a big handicap:
Not knowing the nature of the knower, the human brain.
So we live in exciting times. We're nowhere near the end of the path that leads to full knowledge of the knower. Heck, we may have barely taken a few steps along that path.
But we're vastly more knowledgeable than everyone who has lived before these modern times. Including those revered as spiritual, religious, and mystic adepts. Many of them left us marvelous inspiring insights into the nature of life, living, and the cosmos.
However, we mustn't forget that those accomplishments lacked one important bit of understanding: how the human brain works.