Contretemp-tationsMark Kleiman describes a very common type of situation:
Sometimes people do damage to themselves, or incur the risk of doing so, at the (often not disinterested) prompting of others. Call this pattern "temptation," and the parties the tempted and the tempter. The tempted, and their friends, often blame the tempters for the bad results, and sometimes sue them or demand that the activity of temptation be constrained by law. The tempters, and their friends, always respond that the tempted need to start taking personal responsibility for their actions, and that the tempters can't be held accountable for the foolish acts of others.Mark considers the proposition that "the blamelessness of the tempter follows from the responsibility of the tempted" to be self-evidently fallacious. But he also observes that "many other people" (I am one of them) think this proposition true. So Mark sets out to explain why we think so, and he settles on the idea that we have fallaciously equated moral responsibility with a probability density function, thus concluding that all moral responsibilities must sum to one.
Mark is correct that moral responsibilities need not sum to one. If John shoots Bill while Eric stabs Bill, both are 100% guilty of murder, after all. But disproval of a fallacious argument in favor of a proposition does not disprove the proposition itself, as there may exist other, valid arguments for the proposition. I wish to make one of them.
In involuntary cases like murder and rape, there is little question that a harm has been done, and the main question is one of apportioning punishment. But in voluntary situations - presumably those Mark has in mind, though he declines to name them - the whole issue is whether a harm has actually been done. If I choose to smoke cigarettes, and later I develop lung cancer, this may seem to be, factually speaking, a harm; clearly I'd rather not have cancer. But we must take an all-things-considered perspective, as the risk of lung cancer might have been a cost I was willing to bear because of the perceived advantages of smoking. Likewise for other risky activities, like snow skiing and eating high-cholesterol foods. For there to have been a harm *on net*, the subjective value of costs must have exceeded the subjective value of the benefits - and the only person who is in a position to know is the person who actually experiences them. What we want is a set of legal and moral rules that encourage people to do things that affect their well-being when, and only when, the expected benefits exceed the expected costs. When an individual is held personally responsible for his own voluntary choices that affect his well-being, the costs and benefits are concentrated in one place (his mind), and he thus has an incentive to make the correct choice.
Since moral responsibilities need not sum to one, Mark might argue that we could punish the tempter as well as the tempted when bad results occur. But placing responsibility on the tempter creates a doubly bad incentive: First, if the individual whose well-being is affected is compensated by the other party (as occurs when the damage payments are awarded to the "victim"), his *perceived* costs from the activity are reduced, and as a result he will be more inclined to engage in activities whose costs exceed the benefits. This is the moral hazard problem. Second, the tempter may be deterred from providing opportunities to engage in the activity even when the activity is on net desirable. (This argument holds even if damages are not awarded to the victim.)
There is an exception to the general rule I've stated here, and that occurs when the tempter possesses but withholds information that *might* be relevant to the tempted's decision. If we want to encourage decisions that take into account all costs and benefits, then we need legal and moral rules that encourage disclosure of cost- and benefit-relevant information. This is the source of the one quasi-plausible argument against the tobacco companies in the recent lawsuits: that old enough smokers might have chosen not to smoke if the tobacco companies had been more forthcoming with information they had (and that was not available from other sources) about the health consequences of smoking. (I say "quasi-plausible" because I'm not convinced that potential smokers were really that clueless about the likely effects of smoking, nor that it would have made a difference if they had been informed. But at least the form of the argument is right.)
In short, when the very desirability of an activity is in question, simple causality (in the sense of necessary conditions) is not the relevant issue. It's true that the tempter's offer may be a necessary condition for the outcome to occur - but in order to know whether the outcome is a "harm," it is necessary to consult the preferences of the tempted. Placing moral and legal responsibility on the tempted creates the appropriate incentives to encourage value-increasing and discourage value-decreasing activities, and placing responsibility elsewhere mucks up the decision calculus unless it encourages the dissemination of relevant information.
One final caveat: I am thinking primarily in legal terms, because I'm concerned about how issues like this should be treated as a matter of policy. It's possible Mark wished to restrict his comments to the moral realm only. If so, I might concede that the tempter should "feel bad" and is thus not "blameless." But as soon as we start talking about meting out reward and punishment, whether in the legal realm or otherwise, I fall back on the arguments above.