I suppose I should have something interesting to say about Lisa Randall’s Knocking on Heaven’s Door, which I have finally finished.  But instead I find myself pondering these two sentences from her section on the Large Hadron Collider (LHC):

Nothing substitutes for solid experimental results.  But we physicists haven’t just been sitting on our thumbs for the last quarter century waiting for the LHC to turn on and produce meaningful data.

“Sitting on our thumbs?”  Doesn’t she mean “sitting on our hands”?  Or “sitting around twiddling our thumbs”?  “Sitting on our thumbs” evokes an anatomical image that I find a little distressing.  Did I miss the memo that made this an acceptable cliché?

I decided to ask Mr. Google Ngram Viewer Person, who has helped me in the past.  But he just throws up his hands — or maybe his thumbs.

“Sitting on our hands” showed up around the beginning of the twentieth century and took off in the nineties.  “Sitting on our thumbs” doesn’t even register.

But regular ol’ Mr. Google tells me that “sitting on our hands” currently has 269,000 hits, and “sitting on our thumbs” has a whopping 74,000 hits. So it looks like something’s been happening to the language lately — at least in the unedited wasteland that is the Internet.  (The first hit for “sitting on our thumbs” is from Ann Coulter in 2011.  Good job, Ann!) In every case that I looked at of “sitting on our thumbs”, “sitting on our hands” would have worked just as well, so a lot people just seem to have lost the feel for the older metaphor.

Clichés and dead metaphors are what they are — few people think deeply about them, and “sitting on our thumbs” seems to be completely comprehensible.  So who am I to complain? Time for me to stop being distracted and to return to contemplating the search for the Higgs boson.