Proponents of carbon trading over carbon taxes deny that carbon taxes are more transparent — because you can play any game with a tax you can with a trading system. But the point of transparency is not that games become impossible, but that they become more obvious, and thus easier to stop.

When it comes to handing out permits (grandfathering) rather than auctioning them, carbon tax advocates clearly have the better of this argument.

The equivalent with a carbon tax would be to write big polluters a check — not more difficult in the abstract, but a lot more visible than creating a property right.

“For every one that doeth evil hateth the light…” John 3:20.