Today’s NYT contains an article on Chicago’s proposed trans-fat ban, which I criticized a couple of weeks ago. Most revealing is the chief ban proponent’s response to the argument that the city council should not try to regulate people’s (non-externality-causing) bad habits:
And if the City Council had agreed to simply steer clear of peoplesâ€™ bad habits, said Mr. Burke, an influential alderman who long pushed to ban smoking in indoor public spaces, Chicago might never have passed the smoking ban that went into effect this year….
Alderman Burke’s argument follows perfect modus tollens logic:
(1) If it’s inappropriate for government to force people to be healthy (even if that requires a personal utility sacrifice whose magnitude the government does not know), then the smoking ban was inappropriate.
(2) The smoking ban was not inappropriate.
(3) Therefore, it’s proper for government to force people to be healthy.
Of course, an argument may be valid (i.e., logically correct) but unsound (i.e., wrong) if one of the premises is factually untrue. (See here.) And that’s exactly the case here. For reasons I’ve stated elsewhere (e.g., here and here), step two of Alderman Burke’s syllogism is wrong; smoking bans represent unwise policy, and Chicago’s ban promises to reduce social welfare.
Alderman Burke’s argument also reveals the slipperiness of the slope smoking bans create. If the government can tell private property owners they can’t allow people to light up in their private airspaces (which all patrons have voluntarily entered), then why can’t it tell restaurant patrons that they can’t voluntarily choose to purchase tasty and cheap trans-fatty foods? While slippery slope arguments are frequently pretty unpersuasive (see, e.g., the use of such arguments in the gay marriage debate), the busybodies on the Chicago Board of Aldermen make this particular slippery slope argument look more persuasive all the time.