Daily Inspiration Quote by William Petty

Petty’s line has the cool austerity of a ledger entry pretending to be moral philosophy. “No man pays double” sounds like common sense until you notice the trapdoor in the second clause: “nothing can be spent but once.” He’s not just talking about being overcharged; he’s redefining “cost” as an inescapable, one-time surrender of resources. Money, time, labor, attention - you don’t “keep” them and also “use” them. You convert them, irreversibly, into whatever you choose next.

The intent is disciplinary. Petty, writing in a 17th-century England busy inventing modern finance, taxation, and state capacity, is pushing back against muddled thinking about economic burden. People complain they’re paying twice - in taxes and in prices, in rent and in repairs, in wages and in welfare. Petty’s rebuttal is almost prosecutorial: you can shift who hands over the coin, you can disguise the transaction, you can delay it, but you can’t make society “pay twice” in any literal sense because the unit of sacrifice is singular and final. Once spent, it’s gone; all you can do is argue about where it should have gone.

The subtext is political as much as analytic. By insisting on the one-ness of spending, Petty smuggles in a proto-efficiency ethic: stop performing outrage at “double payment” and start measuring trade-offs. It’s a compact way to steer public debate from grievance to accounting - and, not incidentally, to make state finance feel like nature rather than choice.