What does it mean to be skeptical?

Here’s the etymology of the word:

skeptic (n.) Look up skeptic at Dictionary.comalso sceptic, 1580s, “member of an ancient Greek school that doubted the possibility of real knowledge,” from French sceptique, from Latin scepticus, from Greek skeptikos (plural Skeptikoi “the Skeptics”), literally “inquiring, reflective,” the name taken by the disciples of the Greek philosopher Pyrrho (c.360-c.270 B.C.E.), from skeptesthai “to reflect, look, view” (see scope (n.1)). The extended sense of “one with a doubting attitude” first recorded 1610s. The sk- spelling is an early 17c. Greek revival and is preferred in U.S.

Skeptic does not mean him who doubts, but him who investigates or researches as opposed to him who asserts and thinks that he has found. [Miguel de Unamuno, “Essays and Soliloquies,” 1924]

I was reading the blog of a well-known Australian climate change denier recently – Jo Nova – and a recent post is titled, “Major 30% reduction in modelers [sic] estimates of climate sensitivity (skeptics were right)”. She calls herself skeptical and she’s written a book for skeptics called, “The Skeptic’s Handbook”. Yet if you visit her blog, there’s very little of the inquiry and reflection that you would expect from someone who calls herself skeptical and absolutely no sign of self-doubt. Instead she asserts in this post that “skeptics were right” and “the deniers were ahead of the climate experts”. I am reminded of a Bertrand Russell quote:

“One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision.”

Scientists *are* full of doubts but Jo Nova is not. According to her she’s been right all along. She also mocks scientists for expressing their own doubts. Here’s what she says in response to a section in the paper in which the authors describe the uncertainty:

Translated: we weren’t very sure of things, and we still aren’t, and our new estimates are lower, but we didn’t completely rule this out in the past, so therefore we were really right all along in a vague kind of way.

The most ironic thing about her post is that the paper which she thinks proves that skeptics are right, is a paper that attempts to put a number on how much warming we can expect as a result of human-caused greenhouse gas emissions.  That’s right, a paper that accepts human-caused global warming and attempts to quantify predictions, is somehow proof that (pseudo)skeptics were right.

The paper is called Energy budget constraints on climate response which was published in Nature Geoscience this week. For a good summary of the paper, I recommend this piece in The Guardian by Miles Allen (one of the authors): Matt Ridley has joined the real climate debate or this one by Alexander Otto on the Met Office website.

I don’t think there’s anything in the paper that warrants the salivating response from psuedo-skeptics like Jo Nova. Yes the Earth is warming, yes we’re causing it and yes there’s uncertainty as to exactly what the new temperature will be.