One cannot avoid the conclusion that synapses evolved out of the same mechanisms as multicellularity. What binds bodies together shares the same origins as what binds brains together. https://phys.org/news/2020-06-evolution-synapse.html
What's also very interesting is that there are virus like capsules that preserve information across the bindings. https://massivesci.com/articles/arc-protein-mind-control-memory-brains-shepherd-utah-tedmed-alzheimers/
So this notion of simple and primitive signaling between cells or even signaling between neurons is woefully inadequate. We aren't talking here about primitive analog signaling. Rather, it is much more sophisticated!
That is why, to understand how brains work, we have to realize that its 'selves all the way down'. https://medium.com/intuitionmachine/general-intelligence-via-selves-and-conversations-all-the-way-up-739c0e4d0ca9
If there are selves, then what pray tell are the conversations that go on among themselves? What topics are they talking about? The same thing we talk about, we talk about the subject of life.
That subject involves how to find energy, autocatalyze (reproduce), homeostasis (maintain oneself) and learn. At a certain abstraction level, it's the same thing as what humans talk about!
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