To quote the philosopher Sagan, "Extraordinary claims require extraordinary evidence".
I recognize that large fauna can exist without being known to science.
The
Saola is native to Vietnam and Laos, is a relative of antelopes and wasn't confirmed to exist until 1992.
So one cannot say it is impossible that a large unknown animal could be living in the forests of North America, but the probability for Bigfoot is very low.
The primary problem that if Bigfoot existed, it would be a species of unknown hominid.
There is only one hominid species know to inhabit the Americas, that would be us.
All other primates are monkeys, specifically "New World" monkeys, which is evolutionary distinct from "Old World" monkeys.
So the question becomes, how could this one species of hominid get here (outside of humans) and no others did?
Humans are thought to only have migrated here in the last 15 to 20,000 years, and there is plenty of fossil evidence of humans in Asia, Africa, and Europe prior to that.
If Bigfoot is an unknown Hominid species, where is all the fossil evidence for it in Africa, Asia, or Europe?
Have people seen things in the forest that they can't immediately explain?
I'm sure they have.
But that doesn't "prove" that they saw Bigfoot.
Humans are hardwired to find patterns and fit things in categories.
Think about it. People look at clouds and see shapes of animals, people, etc. People see Elvis, Jesus, Mary, etc. in their toast, the stain on a wall, the bark of a tree, etc.
We do this fore a very good reason.
The little primate very much in the before time that spotted the pattern of the lion in the grass lived to breed more little primates. The one that didn't, was lunch.
By the same token, putting things in categories helps stay alive as well. recognizing something is only half the step to escaping the lion, knowing what to do matters more.
So you have to categorize things, to know which patterns mean you found lunch, vs those that mean you are lunch.
IMHO, this hardwiring is responsible for the vast majority of conspiracy theories, beliefs in ancient aliens, UFO, paranormal, etc.
Yes, there may be an incident here or there that may warrant being investigated as a legitimate phenomena/event, but the vast majority are pattern matching and categorization run amok.
Take UFO's as an example.
OK, let's assume that there is a completely inexplicable sighting of something in the air.
Then by definition, it is an "unidentified flying object".
So how did that mean that it is a flying saucer filled with space aliens?
That is the sole possible explanation for something we don't know what it is?
That's because we are hardwired to put it in a category. "Unknown" just doesn't cut it.
BTW, IMHO, most of the "inexplicable" UFO signings could well be Ball Lightning.
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