1. igor_kolesnikov says:

yes, probably because a person at the mention of a crow represents first of all the black color, therefore, when mentioning the white color, you do not immediately imagine the black color(crow), so the confidence that white can be a crow is a closer thought

1. Say the word blood ten times.
2.1. What leaks if you cut your finger?
2.2. What runs through your veins?
2.3. What pumps the heart?
3. At what light can you cross the road?

How about a red light? And at school they teach that on green!

2. valera_dubilet says:

Even simple “everyday” logic tells us that if “A”, then there can not be “not “A” at the same time.
For example, if it's night, it can't be “not night” (morning, evening, or afternoon), if I'm walking, I can't simultaneously “not walk” (lie down, run, etc.)
This is how one of the laws of logic manifests itself – the law of the excluded third: either “A” or “not” A”, there can be no third.

Now let's “reverse” our ” formula.
We said that if “A”, then not ” not “A”.
So the opposite is also true: if not ” not “A”, then “A”.
That is, if” A “is” Andrey climbs”, then any ” not ” A ” (“Andrey does not go”, “does not go”, “does not sit”,” does not lie”, etc.), will confirm/prove our”A”.
You can even play the game ” What does Andrey do?”, in which you can use “not “A” to try to determine “A”: “Andrey sleeps? “” No.” ” Andrey reads?” “No.” ” Andrey swims? “” No ” etc. right up to ” Does Andrey climb?”

Now, to get closer to the raven paradox, let's complicate the situation. We considered the construction “A” – not “A”, but everything we said will also be true for the “double” construction: either “A and B” or “not A and not B”, that is, it turns out that any “not A and not B” indirectly confirms “A and B”.
Logically, this is absolutely correct, but from a “vital” point of view, it is strange: it turns out that the fact that Vasya drinks and Masha walks confirms/proves that Andrey climbs.