The fifth Philosophers' Carnival is up at Ciceronian Review. There are some interesting posts this time around. The post from Prosthesis on science and beauty is very interesting, and reminds me of Stephen J. Gould's work towards the end of his life (leading to this book, and research at this lab). It's hard to tell whether the author of the post at Prosthesis thinks "nonempirical" factors in theory selection are bad for science, but it's clear that he/she thinks they are unavoidable. I like Gould's take, in which nonempirical (most notably aesthetic) factors are not only inevitable, but desirable. Science is about understanding the world around us, after all, and aesthetic considerations can facilitate understanding.
Blowhard has a very good introduction to Stephen Toulmin, whom I only recently really discovered, so I found the post helpful.
Siris, which continues to be one of my favorite blogs, has a good post on Shepherd on causation. I don't really know anything about Shepherd, and I've only really begun to think seriously about causation, so this post was definitely edifying for me.
I also liked the post at Evolving Thoughts on knowledge of the past in science. The issues discussed in the post don't really come up in my own work as problems with scientific knowledge, but similar issues are raised when trying to verify the accuracy of memories. For instance, in the debate over recovered memories, what evidence constitutes verification of the accuracy of the content of recovered memories? Unlike in the sciences, immediate certainty is important here, because the future discovery of new evidence may come too late. For instance, when recovered memories are used as the primary evidence in criminal cases against accused child molestors, we can't wait until after the trial to decide whether the recovered memories are accurate.
There are several other interesting posts in this edition of the Carnival as well, so go check them out.