Earlier quoted context omitted.
Because we exist. Admittedly, "healthy enough to procreate" is not a high bar, but it's pretty good in comparison with no bar at all. Yeah, there are cases where they were unaware of the harm--like lead. We should absolutely be finding better ways to identify and mitigate harms of that sort. But in the absence of reliable information from such efforts, natural==safe is a viable heuristic. And I'd say that our scienti…
I think natural==safe is a terrible heuristic for the exact reason you said. Healthy enough to procreate is a low bar, and many natural things provide a benefit in terms of procreation but detrimental to health. Almost everything in nature is a trade-off between how much it'll harm you and how much it'll help you procreate. This reminds me of how whales get the Bends from diving despite 50 million years of evolution.…
Maybe... but many more either kill you or they don't. Lets take your whales-getting-the-bends example. That gives us a dimension: pressure. Suppose you're whale.
- Let x be a randomly chosen pressure
- Let y be a pressure that your parents lived through
You have to spend a few minutes at x or y, which pressure do you chose? y would be a safer choice.
The same goes for potentially hazardous chemicals: the safer bet is to pick the one that comes with evidence that things like you can survive contact with it, and that'll be the one that was in your environment when you were born. Otherwise you wouldn't have been born there.
If somebody wants to sell us something that our parents never came in contact with, the evidence that it is safe should be stronger than the effect described above. I'm not a statistician, so I can't quantify that effect, but it exists, and the naturalistic fallacy distracts from it.