Re: how much knowledge

The oxford english dictionary has something like 2.4 million word
usages.
That doesnt include technical definitions nor those present in
non-English languages.
An educated person may only a know 2-3 hundred thousand of these
meanings.

The CYC project (www.cyc.com) is probably the most ambitious 20-year
attempt
to capture concepts in a computer. It organizes these in several ways
including fact-like and inference-like techniques. I see the phrase
"hundreds of thousands of assertions" in their web description.
And still users complain of gaps.