Benjamin’s dollar is a symbol, and no one has much of an interest in changing it. Imagine the dreary debate that would ensue if a designer, in a more official context, would propose removing, as Purrington has, the phrase “in God we trust.”

Purrington is thinking ambitiously. The design, he says, is partly about “being able to look at ourselves as human beings outside of ourselves on a very large scale.” It’s a kind of humanistic, secular, highly scientific outlook on the world that believes in progress based on human reason.

And it delivers that, in a way. The front of the $5 banknote is a human neural network. Like the other bills, a braille numeral is printed in raised dots on the bottom right corner. A Treasury Department logo serves as a focal point. In widely kerned lettering, the note reads: “This currency is upheld by the integrity of its people.”