One of the silliest trends in state and local government — and I’m here to tell you, there are very many silly trends — is for politicians to sell new taxes to fund arts facilities and programs as if they were “cultural investments” that pay economic dividends. Years ago, someone came up with the absurd, Keynes-gone-wild proposition that every dollar spent on arts programs returned $6 in local economic returns. After this factoid made the rounds a few times, it had mutated into $8, then $11. Opera companies and radical puppet shows, it seems, had become magical money machines.

The most recent production of the “culture tax” show opened today in Philadelphia. Mayoral candidate Bob Brady has announced a plan to impose an additional tax on development — technically it’s a one-percent set-aside for firms receiving tax-increment financing, but for reasons too complex to go into here this is essentially a new government exaction — to fund an endowment for arts and cultural groups. Brady says that the policy would generate $45 million annually for the endowment, and cites a recent study by the RAND Corporation to the effect that Philadelphia is no longer “competitive” with other big cities in its cultural investment. The Philadelphia Inquirer loves the idea, of course. The editorialist envies Pittsburgh and Denver, where politicians “long ago mustered the political will to enact regional cultural taxes.”

I’m no foe the arts. I’ve spent much of my life in artistic pursuits. But this is sheer nonsense. Sure, all other things being equal, a corporate executive, entrepreneur, or “creative class” type might take notice of the existence or absence of a favorite artistic offering when deciding where to live and work. But all other, more-important things are rarely equal. How much could $45 million a year, invested wisely, help to make Philadelphia a safer city? How much road maintenance and expansion would that finance? Or, alternatively, how might those who earned the $45 million in the first place spend their own money, and how many jobs and economic opportunities might that create?

Art is its own end. It should be produced or consumed on its own terms. In the meantime, catch criminals, fix the bloody potholes, and let people keep their own money.