Agreed. An 11 foot man is supposed to increase your CONFIDENCE that there are no 12 foot men, just as all non-black objects which are not ravens increase your confidence that all ravens ARE black.
But confidence is all it is. It's not a proof. A single albino raven would constitute a disproof.
What's funny about the 11 foot man is that it, logically, SHOULD increase your confidence but actually decreases it.
Raven paradox
Benjamin White
Mason Brown
That's easy. All I need is a nutcracket and some cooperation on the part of the guy whose mind needs changing.
Ryder Gomez
>I think in daily life people would never accept a handful of grapes as being evidence of anything at all about ravens.
That's because it's infinitesimally compelling evidence, which means it effectively isn't evidence.
The total number of non-ravens is in fact infinite because there's no limit on what you can identify as an object that counts as a non-raven. You could count abstract objects for example and then you wouldn't even be bound by real world physicality, or you could count just real world objects but use an infinite number of different approaches to classifying them e.g. a chair vs. the assembly parts of a chair like its legs vs. the wood of the chair vs. the molecules of the wood vs. the atoms of the molecules etc.
So while both:
A) An instance of an observed black raven and
B) An instance of an observed non-black non-raven
Would both technically be evidence for the claim, A would be a real number weighted amount of evidence (~16 million ravens in the world) while B would be a 1/ω weighted amount of evidence, which for most purposes means B is equivalent to zero evidence.
This explains why people don't intuitively think grapes say anything about the claim all ravens are black. Their intuition in this case is effectively true, equating 1/ω with 0 is something done formally all the time, and certainly acceptable for people to do informally in assessing what counts as evidence for a claim.