I think he knows it, but he won't accept he's wrong.
He also somehow manages to paint himself in a good picture, like he knows the truth... meanwhile he thinks vaccines are bad for you, among other crazy things with absolutely 0 proof at all. The whole argument was really draining and I stopped taking him seriously for a while until I just responded last week to his "sources"
You can just read the whole argument to see his side. (I was actually pretty rude earlier in the argument)
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