Very welcome! Alexander is an interesting writer, and his book reviews are some of his most useful stuff (he manages to simultaneously excite me about reading the book and make me feel like I don't need to, because the review was so thorough). Like Zvi above (they're friends), Alexander is a big deal in the Rationalist community and has most of the good and bad you might expect from that, though I think he's a little better about having some humility about his conclusions than some, and he's also pretty funny at times, which certainly helps. A couple of his other greatest hits: "Meditations on Moloch" (https://slatestarcodex.com/2014/07/30/meditations-on-moloch/) and "The Categories Were Made for Man, Not Man for the Categories" (https://slatestarcodex.com/2014/11/21/the-categories-were-made-for-man-not-man-for-the-categories/)

That being said, since getting serious about spirituality, I've found his and other hardcore materialist writings less compelling than I once did.