I'm not sure what this has to do with rationality quotes, but the extract basically convinces me to avoid the guy like the plague. The underlying premises seem to be something like:

• The remaining choice when someone knows enough to feel a book is too simple for them is that they know everything.

• They should discard all that they know - empty before you fill - so they can learn from someone with more knowledge than them.

• Go learn lisp... -shrug-

It seems incredibly bad advice to give to someone who thinks a lot of what's in a book's too simple for them to essentially yell at them to shut up and knuckle down. As compared to say, pointing them to a few things that are generally not covered that well in self-learning and direct them to a more advanced book.