Dionysius Theory — Brady Haran

This week we posted a Numberphile video about a mysterious drawing by John Herschel, contained in a letter to his friend Charles Babbage.

Herschel challenged Babbage to "interpret this hieroglyphic, it contains a great discovery."

A devil-like figure, surrounded by complicated squiggles and equations, was captioned as "Dionysius the God of Functions, alias the genius of numerical magnitude".

Numerous viewers have shared their theories about what it may mean.

But the most promising I've seen so far came from user david getsout who said:

"Back in the day dionysius lardner was a professor at london working with hershel to build big telescopes dionysius would talk shit about the infinate universe and us being at the center due to human perception or somthing complicated like that."
(SIC)

I had never heard of Lardner, but some quick Wikipedia and Googling shed more light on matters.

Lardner sounds like a science populariser and commented/lectured on the work of people like Babbage and Herschel.

I can easily envisage two scientists being a bit snarky toward someone who does that. It is not uncommon these days!

Was Herschel (left) mocking Lardner (right)?

It may also explain why Herschel spells it Dionysius with an "i" and not Dionysus which is how the God of Wine is spelled? But I don't know much about the history of this word.

I look forward to more investigative work by keen-eyed and clever viewers.