Digital Sextant

Weird Things

Critical Thinking for a New Age; by Theodore Schick, Jr and Lewis Vaughn

How to Think About Weird Things was recommended as a primer on diagnosing Woo by Orac over at Scienceblogs. As someone who finds himself more and more irritated by irrational thinking (despite my own gaping biases that lead to it), I was really interested in reading this book. Thus, I read a text book for fun. Sigh, I think there’s a new level of nerdiness there.

Schick and Vaughn lay out a number of key arguments for how and why one should wield the tools of critical thinking to understand the essence of arguments and ideas being offered in the public sphere. I transcribe the key ideas below. Much of this is verbatim from their book. My commentary is in italics

They discuss how to understand claims being made. Namely, just because a claim: is possible doesn’t mean it’s true; hasn’t been refuted doesn’t mean it’s true; hasn’t been proven doesn’t mean it’s false; can’t be explained doesn’t mean it’s supernatural; is possible doesn’t mean it’s real. In other words, people often argue that things aren’t conclusively proven and are thus open to interpretation. While this is true, the authors lean heavily on the idea that we must consider the best conclusions, not just the possible ones.

Truth in personal experience. Just because something seems (feels, appears) real doesn’t mean it is. But it is reasonable to accept personal experience as reliable evidence only if there’s no reason to doubt its reliability. The authors outline a lot of ways our own perceptions fool us. My favorite part of this is selective attention, which gives us the idea that things like The Lunar Effect are true (it isn’t). We look to confirm ideas we already have.

Relativism, Truth, and Reality. Schick and Vaughn obliterate the idea that reality is relative with incisive logic. Just because you individually or a group of people believe something to be true doesn’t mean that it is. There is an external reality that is independent of our representations of it. They critique cultural relativism by suggesting that one cannot posit the truth of cultural relativism without rising above that very phenomenon.

Knowledge, belief, and evidence. There is a good reason to doubt a proposition if it conflicts with other propositions we have good reason to believe, the more such conflicts, the more reason to doubt. We should proportion our belief to the evidence when there is good reason to doubt. Here’s my favorite: There is good reason to doubt a proposition if it conflicts with expert opinion. There has always been a suspicion of expertise, but my guess is this becomes the hardest pill to swallow in the age of Google University. Experts in one field are not experts in all fields. Creationists, take note: A PhD in Geology or Physics does not a Biologist make.

Evidence and Inference. When evaluating a claim, look for disconfirming as well as confirming evidence. This chapter also spends quite a bit of time on Deduction, Induction, and Abduction. Nothing about Conduction, sorry Ulmer.

Science and its pretenders. If you were to read just one chapter, this is the one to read. The authors dig into the way science works and why pseudo-science doesn’t work and how it adopts the rhetoric of science without the rigor. Schick and Vaughn create a heuristic they call the “Criteria of Adequacy.” In short:

The amount of understanding produced by a theory is determined by how well it meets the criteria of adequacy–testability, fruitfulness, scope, simplicity, conservatism–because these criteria indicate the extent to which a theory systematizes and unifies our knowledge. (172)

Testability means it predicts something other than what it explains; fruitfulness refers to the bonus predictions that come from it — this is a plus but not a necessity; scope refers to the diversity of the phenomena it explains — the more the better; simplicity refers to the assumptions it makes — the fewer new assumptions, the better; conservatism means it conflicts with as little background information as possible.

The Evolution vs. Creation debate illustrates these principles nicely.

• Testability: Evolution can be tested against fossil records, against genetic material, and in labs with small organisms. Creation can be tested in the same ways (and has come up lacking). (E 1, C 1)
• Fruitfulness: evolution predicted a number of novel things, including DNA. Creation has not yielded such predictions. (E 2, C 1)
• Scope: Both theories explain a huge swath of science study. (E 3, C 2)
• Simplicity: Evolution relies solely on natural mechanisms we know exist and can observe. Creationism relies on “Special creation,” an unrecorded and non-repeating act by a supernatural diety. (E 4, C 2)
• Conservatism: Evolution fits with other scientific observations about the world, such as the life-span of the Earth. Creationism overturns many of these as well. (E 5, C 2)

Thus, Evolution fits all the criteria for accepting a scientific theory, while Creationism does not. One of the elements of creationism, testability, actually works against it since people have attempted the tests and failed to find anything useful.

The last couple chapters are devoted to case studies of miracle cures and other ideas generally not accepted by science. It’s a great book for people interested in the science/secular split.