No, you just probably never thought about what "knowing" actually means. Put simply, he wasn't there when Washington was President so he can only believe that historical resources are telling the truth.
You have just successfully banished the word by stripping it of any legitimate usage.
Since it was quite a useful word that will undoubtedly be missed, why not being it back with a simple redefinition. We could redefine it as "close enough to true that only a philosopher would object". Then we could continue to use the word, despite the obnoxious objections of philosophers.
Epistemology may be all very neat and interesting, but in the real world there is little place for it. We frequently need to express ideas that may not necessarily be "philosophically pure", in order to get shit done in a timely manner. Think of the concept of "fact" as foma.
Of course I'm not nitpicking on every usage of the word, but I think it's everyone should at some point think about what knowing and reality actually is. It doesn't matter most of the time, but there are moments in history when someone wants to tell you that 2+2=5 https://en.wikipedia.org/wiki/2_%2B_2_%3D_5
> "Of course I'm not nitpicking on every usage of the word"
It is great that you aren't. The issue is that the author of the article was nitpicking a non-controversial use of the word. His son's responses to him suggest to me that his son was sick of his philosophical shit and just wanted to deal with the world pragmatically. Most people have little patience for epistemology, and I find it hard to blame them.
