In an Amazon review of the 2013 book Creation, written by former Nature editor Adam Rutherford, one critic takes issue with what he describes as the work’s “wordy trickery”. “I lost count,” the reviewer complains, “of the number of times that an obscure word or metaphor was helicoptered in.”

Supplied by airlift or not, the online grumble illustrates both the irritation that some feel at analogies and metaphor in scientific writing, as well as the ease with which they can be, ahem, helicoptered in. It’s a debate as old as, well, the hills. And one revived in a Comment article on page 523 that fizzes with … [That’s enough metaphors — Ed.].

In the piece, Eleonore Pauwels, a public-policy researcher in the Science and Technology Innovation Program at the Woodrow Wilson International Center for Scholars in Washington DC, argues that biologists confuse the public when they borrow terms from engineering. Turning on genetic switches and assembling molecular components are processes that are more complex and ill-defined than the imagery might suggest, she says.

Metaphors, writers insist, breathe life into scientific language. But that is the problem, others say. The tendency to anthropomorphize the natural world was dubbed the “pathetic fallacy” by the nineteenth-century art critic John Ruskin. He would have hated the selfish gene.

Still, metaphor has a legitimate place in science. The idea that electrons orbit the nucleus like planets go around the Sun sets up testable hypotheses. Perhaps the problems come when scientific metaphors seek points for artistry rather than aiming for the quiet satisfaction of a job well done.

The English poet John Donne (1572–1631) famously compared the bound souls of lovers to a pair of compasses. “If they be two, they are two so / As stiff twin compasses are two.” To compare a pair of compasses to the souls of lovers, however, would be wordy trickery too far.