Yeah the author is a philosophy prof apparently, so it seems like some of his arguments are considering philosophical positions about epistemology more than real world positions. I do think that it provides some insight into possible problems with hyper-rationalist thinking in other areas of life, though.

Also, I think his analogy about witness testimony is probably flawed like you say, but I think the point stands. We often know things without really being able to articulate why or how we know them. Our brains are fantastically complex machines and it can be difficult or impossible to interrogate every step of our thinking, particularly when intuitive or tacit knowledge are involved.

I also really appreciate that he drills down on the problems associated with axiomatic thinking - that one can use deductive reasoning from a few simple “self-evident” principles to derive an entire philosophical or moral system. It’s an appealing idea, but I think it leads to a lot of problems.