> All cats are white.
> All the cats I see are black.
The second statement doesn't actually imply that all cats are black but it does refute that all cats are white. It doesn't make it's own claim about all cats, it just adds an anecdote that doesn't conform to the first statement.
However, the original argument regarding smoking bias is correct of course.
> All cats are white.
> All the cats I see are black.
The second statement doesn't actually imply that all cats are black but it does refute that all cats are white. It doesn't make it's own claim about all cats, it just adds an anecdote that doesn't conform to the first statement.