The more I read that, the less sense it makes. Are we to conclude that Dawkins is as wrong about evolution as the Intelligent Design proponents? Is there the slightest reason to think that whatever source Landsburg is paraphrasing as "for Dawkins, complexity can arise only from simplicity", Dawkins had anything but evolution in mind? What has the ontological status of arithmetic to do with how present-day lifeforms came to be? What does any of this have to do with rationality?
Landsburg does not doubt biological evolution. It's just an argument about complexity being inherent in the laws of nature, reality. And what it has to do with rationality, it's thought provoking. And rationality is a means to an end in succeeding to reach your goals. If your goal is to fathom the nature of reality these thoughts are valid as they add to the pile of possibilities being worthy of consideration in this regard.
A monthly thread for posting rationality-related quotes you've seen recently (or had stored in your quotesfile for ages).
ETA: It would seem that rationality quotes are no longer desired. After several days this thread stands voted into the negatives. Wolud whoever chose to to downvote this below 0 would care to express their disapproval of the regular quotes tradition more explicitly? Or perhaps they may like to browse around for some alternative posts that they could downvote instead of this one? Or, since we're in the business of quotation, they could "come on if they think they're hard enough!"