Some sciences aren't absolute, like the social sciences. I could site studies where children who are exposed to sex at an early age go on to lead traumatized lives, but that's all anecdotal evidence as such studies are subjective and hard to control.
Just because it has been shown that one of a set satisfies a given property, does not mean all of that set satisfy that property. Just because you've never met an immortal, doesn't mean they don't exist. So your argument that all humans die is fallacious and a result of your own anecdotal evidence.