The lateralization ("difference in behavior") of mammalian brain hemispheres varies, is high in birds, low in cats, but is extreme in humans.
Our two hemispheres do not see the same. Generally, the right hemisphere accepts signals from both left and right senses, but the left hemisphere actively pretends that one side is irrelevant. Due to neuronal fiber crossing, the left hemisphere controls the right side of our body and vice versa. And in the middle junction of our brain, the corpus callosum, the left hemisphere ALMOST ONLY sends inhibitory signals— "Shut up I don't want to hear what you're talking about shut up! I already know the truth!".
In patients who have brain injuries only in their right hemispheres, this results in incredibly bizarre behavior:
  • The patient will only shave half his face (the right side).
  • When asked to describe his surrounding, he will only describe the right, and when directed to look at the left, it causes annoyance and dismissal.
  • (best o all) The patient, when directed to look at / hold up his left (ignored) hand, and then asked e.g. "Why are you holding it like that?", the patient responds confidently "That's not my hand": The more you point out things such as "But it is attached to you, it must be your hand", the more annoyed they become and do not accept the idea.
This is only true if you damage the right hemisphere: If the damage was on the left side, you'd be a (nearly) fully functioning person.
The great thinker Iain McGilchrist (great vids, but I recommend his book Master & His Emissary for the full picture) has studied this laterealization in many other species.
He argues that the reason we have these two VERY SEPARATE systems of perception ("ways of handling reality") is because animals need to solve a very specific problem. We need to hunt, which requires "DETAILED FOCUS", at the same time that we need to not be killed by predators, which requires "BROAD CONTEXTUAL AWARENESS".
The behavior is completely apparent in birds; They actually turn their head and use the other eye depending on if they're trying to look at a predator or prey.
To quote the man, who by the way also believes that our society has veered off course and begun letting our leftern hemispheres dominate too much:
"You could say, to sum up a vastly complex matter in a phrase, that the brain's left hemisphere is designed to help us ap-prehend – and thus manipulate – the world; the right hemisphere to com-prehend it – see it all for what it is. [...] nowadays we live no longer in the presence of the world, but rather in a re-presentation of it. The significance of that is that the left hemisphere’s task is to 're-present' what first 'presences' to the right hemisphere."
Wonder if this has anything to do with the ability of human beings to not understand/apprehend things that are not to their advantage. For instance, owners and workers at steel mills will argue convincingly (and will themselves believe) that tariffs on steel imports are very important.
"It is difficult to get a man to understand something, when his salary depends on his not understanding it.” ― Upton Sinclair
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I don't know anything about steel tariffs, trying to make sense of this. A tariff is a tax on importing? and both workers and owners of steel processing places, places that buy steel and process it and sell it, they WANT TARIFFS???? Seriously this is the craziest thing I've heard in a long while, I'll give 2k sats to anyone who can explain it even a little!
Are they just patriotic and believe in supporting local mines?
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Yep, they want tariffs. Say US steel producers (producers, not consumers) can sell steel to companies that make products which need steel (like appliances and cars), for $100 a ton. Companies in Asia may have lower costs, and can sell the same steel for $50 a ton.
But if the companies in Asia are hit by a $75 per ton tariff, they can't make a profit. So the US producers - both owners and workers - win. And consumers pay more.
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I forgot about the part where people working at steel CONSUMING business lose their jobs.
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Fascinating. Thank you!
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Thanks for the zap! BTW can anyone explain why on some zaps I earn what seems like 90%, but on others, it appears to be 25%? Is that written up somewhere?
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