Slip sliding

Richard Thaler writes about "Slippery-Slope Logic" in this morning's NY Times. Slippery slopes are rhetorical devices.  As such, they may be good conversation starters, but that is all.  I get that. 

Thaler takes aim at Justic Scalia's "broccoli" comment during the recent oral arguments before the Court over Obamacare.  He ends this way:

More generally, we would be better off as a society if we could collectively agree to ignore all slippery-slope arguments that aren’t accompanied by evidence that said slope exists. If you are opposed to a policy, state your case based on the merits — not on the imagined risk of what else might happen down the road. The path of that road is so unpredictable that it may even produce a U-turn.

But on the other side of the discussion, look at Robert Levy and William Mellor's The Dirty Dozen: How Twelve Supreme Court Cases Radically Expanded Government and Eroded Freedom.  This is from their conclusion:

Over the past seven decades, the U.S. Supreme Court has rewritted major parts of our Constitution, including the General Welfare Clause, Commerce Clause, Contracts Clause, Non-Delegation Doctrine, and the First, Second, Fourth, Fifth and Fourteenth Amendments.

Constitional law is not my field, but the authors' case-by-case analysis of the "Dirty Dozen" is eye-opening.  I even wish that there had been more attention to slippery slopes over the past seven decades.