"…some of the same lawyers who spent years battling tobacco companies
on behalf of sick smokers […] are arguing that the fast food industry
is a similar risk to public health."
CNN.com, August 19 2002

Several lawsuits have already been filed against fast-food restaurants, claiming
that they are responsible for the ill health of the obese who have fed for years
on their products. None have so far been successful, and many people regard them as
some kind of joke. But advocates point out that the first people to sue "big
tobacco" were ridiculed. Yet in 1998, the Master
Settlement Agreement saw the major US tobacco companies agree to pay $246bn
over 25 years to settle lawsuits filed by US states.

The success of the tobacco suits has encouraged those who believe that the
junk-food claims are analogous. In both cases, it is claimed that public health
has been damaged by the actions of major corporations who concealed the health
risks of their products. This makes them liable to pay damages to those who
suffered as a result.

From a legal point of view, there are certainly precedents set by the tobacco
suits which those pursuing fast-food manufacturers will want to learn from.
But are the two cases truly analogous?

One legitimate way to draw an analogy in an argument is to identify a common
logical structure. In such a case, it is not the content of the analogy that
matters, but the structure of the inference. So, for example, it can be argued
that the arguments against the tobacco and fast-food industries have a common
structure, namely:

1. If a manufacturer covers up the harm its products can cause, it is responsible
for any such harm its products do cause.
2. X has covered up the harm its products can cause.
3. Therefore X is responsible for any such harm its products have caused.

If (1) is true, then X can be substituted for anything which makes (2) true
and the conclusion (3) will follow. In this way, the two arguments are analogous.
In fact, they both share a basic valid form known as affirming the antecedent:

If P then Q
P
Therefore Q

But the tobacco case is not cited purely because the arguments there have the
same logical structure. Rather, it is claimed that the relevant facts are the
same. In other words, the similarity extends to the content of the premises.

This is where the analogy might break down, at least with the specific argument
considered above. First, it is not clear that the Master Settlement Agreement
was premised on the principle that "If a manufacturer covers up the harm
its products can cause, it is responsible for any such harm its products do
cause". But even if it were, the second premise – X has covered up the
harm its products can cause – is almost certainly not equally true of the tobacco
and fast food industries.

It should have been obvious to tobacco companies a long time ago that their
products were intrinsically damaging to health. Warnings such as those now placed
in adverts by the alcohol industry – "use our product responsibly"
– would be incongruous on cigarette packets. But fast-food, like alcohol, can
be enjoyed in moderation without harm to health. And furthermore, the facts
about what constitutes a healthy diet are well enough known for it to be possible
to make the case that consumers should choose for themselves how much fast-food
they consume.

The complaints that can be made against the tobacco firms and the fast-food
restaurants are thus disanalogous. Cigarette manufacturers are accused of not
making public the at the time little known risks of using their products; fast-food
manufacturers are accused of not doing enough to highlight the well-known risks
of misusing of their products. In one case, it’s about covering up the inevitable
harm, in the other it’s failure to advertise the potential harm caused by misuse.
Hence the second premise of the argument is not the same in both cases and the
analogy breaks down.

When determining whether an analogy is a good one, sometimes the main point
being made is about the logic of the argument and it is just the structural
similarities which count. But in other cases, such as this one, the relevant
similarities must extend to contents of the premises if the argument is to be
analogous.

However, what is interesting is that the analogy would become much closer if
it could be shown that the fast-food manufacturers were concealing little-known
facts about the dangers of their products. There would still be a difference,
in that a healthy lifestyle can include moderate fast-food consumption, whereas
it cannot include moderate smoking. But if legally the key concern is preventing
information reaching the public domain, the analogy might nevertheless be close
enough for some lawsuits to succeed.