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Drought in Brazil's Amazon reveals ancient engravings

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Re: Drought in Brazil's Amazon reveals ancient engravings

#31

People generally dont know it, but the facts/debate around the sophistication of populations thousands of years ago, and how those vary across geographies, is extremely political. There is generally an unseen hand that dictates the narrative around the distant human past. You can pull the facts together, but the full picture is almost never presented cohesively to the non academic population.

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Re: Drought in Brazil's Amazon reveals ancient engravings

#32

Engravings that are 2,000 years old: so the river was (at least) this low without the current climate change, no?

This is a good opportunity to point out this strategy of climate denial, and why it is not a rational approach to refuting climate change.

Let's suppose that all the other commenters are wrong, that the river has not changed course in the past. The implication, from a probabilistic perspective is that P(evidence|climate change) is the same as P(evidence| natural variation), and your implied assumption is that because your prior belief that no climate change is more likely than climate change, then this works ultimately as evidence in favor that there is no climate change.

The reason this does not yield interesting results, even if all these other assumptions we're making hold, is because the hypothesis of climate change doesn't simply explain this one observation, it explain an enormous range of phenomena.

To explain away all of the observations explained by climate change you end up building a huge list of different hypotheses to explain away each fact. Even if individually these alternate hypothesis do explain each piece of evidence better (which in practice they often don't), and even if your prior for all of these other hypotheses is higher than climate change, because climate change is a single hypothesis that explains many observations, the joint probability of the individual hypothesis quickly becomes much lower than the climate change hypothesis.

In order to effectively argue against climate change you would need a competing singular hypothesis (or small set of very likely hypotheses) that ultimate do a better job explaining all of the observations we have collected.

I don't know if this fallacy has a name, but it sure should since it comes up in a lot of arguments about systemic problems.

Re: Drought in Brazil's Amazon reveals ancient engravings

#33

People generally dont know it, but the facts/debate around the sophistication of populations thousands of years ago, and how those vary across geographies, is extremely political. There is generally an unseen hand that dictates the narrative around the distant human past. You can pull the facts together, but the full picture is almost never presented cohesively to the non academic population.

Wherever the popular narrative goes, there is also a huge amount of real uncertainty about the sophistication of the people that lived at the prehistoric Amazon.

The forest hides and destroys stuff extremely well.

Re: Drought in Brazil's Amazon reveals ancient engravings

#34

Engravings that are 2,000 years old: so the river was (at least) this low without the current climate change, no?

This is a good opportunity to point out this strategy of climate denial, and why it is not a rational approach to refuting climate change. Let's suppose that all the other commenters are wrong, that the river has not changed course in the past. The implication, from a probabilistic perspective is that P(evidence|climate change) is the same as P(evidence| natural variation), and your implied assumption is that because…

I don't think it's a fallacy, as such - it's more like a wilful failure to apply Occam's Razor. Great comment, by the way.

Re: Drought in Brazil's Amazon reveals ancient engravings

#35
post #17

Earlier quoted context omitted.

Even with all the information at our fingertips, I still don't know what a person dreams of, hopes for, cries about, longs for, and ultimately, who the person really, truly, is, because us humans are all too good at sharing everything, but the truth of our humanity, the things that make us vulnerable, so we invent a shallow shell of a personality over the years to protect ourselves and thus we put out there only that…

and on the inside of that shell, we're all pretty much the same...

Looking at Roman graffiti from 2000 years ago does pretty much confirm this.

Re: Drought in Brazil's Amazon reveals ancient engravings

#36
post #16

Earlier quoted context omitted.

Like horses in the Americas. There is a narrative that horses were in the Americas, then died off, then were reintroduced by Spanish conquistadors. But, there is sporadic evidence that horses did exist in the Americas the entire time.

Mind sharing a link to that evidence?

A representative example of the sporadic evidence mentioned is here: https://news.ycombinator.com/item?id=38017332

Re: Drought in Brazil's Amazon reveals ancient engravings

#37
post #9

Earlier quoted context omitted.

How so?

Like horses in the Americas. There is a narrative that horses were in the Americas, then died off, then were reintroduced by Spanish conquistadors. But, there is sporadic evidence that horses did exist in the Americas the entire time.

If this were true, surely it would be impossible to miss the genetic markers in modern American horses.

Re: Drought in Brazil's Amazon reveals ancient engravings

#38

Engravings that are 2,000 years old: so the river was (at least) this low without the current climate change, no?

There have been droughts in the past. But a drought in the past would be no proof that climate change is not real.

Therefore, a drought in the present would be no proof that climate change is real.

Re: Drought in Brazil's Amazon reveals ancient engravings

#39
post #16

Earlier quoted context omitted.

Mind sharing a link to that evidence?

A representative example of the sporadic evidence mentioned is here: https://news.ycombinator.com/item?id=38017332

That, sir, was good fun!
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