Philosophers have disagreed about whether Hume is right. Here are some of the more common reasons given for thinking that Hume was mistaken.
There have been times when scientists thought that something was a law of nature but discovered that they were mistaken. If Hume is right, how could this be? How can we ever discover that we were mistaken about what we thought was a law of nature?
Well, there are a couple of ways we can imagine this happening. One way involves a wholesale rejection of a law of
nature and all, or virtually all, of the observations which support it. Someone, for example, might argue that there is nothing like a law of gravity, and all of our apparent experiences of things (including Samoans) falling down rather than up, let’s say, were really hallucinations. Obviously, this is never going to happen. Mistakes about the laws of nature tend not to be this dramatic. But even if this did happen, one would have to be able to describe repeatable experiments showing that it were so for it to be reasonable to believe. For instance, perhaps one could show that it were true by explaining the mechanism that caused the hallucination, and then showing how anyone could come to see how things really are by being given an antidote to whatever is causing the hallucination. In this case, the quality of the evidence for the claim that we hallucinated might well outweigh the quantity of evidence we have that something like gravity is at work. I don’t think this is at odds with the spirit of Hume’s argument. After all, we are simply weighing the evidence, and taking into account its quantity and quality, as Hume suggests.
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But revisions to laws of nature don’t usually work this way nowadays. What is more likely to happen is that we discover that what we thought was a regularity throughout nature is only a regularity in less than extreme conditions. Scientists do not reject a law of nature by discovering situations where the law ordinarily does hold, was suspended once or twice, but still holds. Rather, they discover new conditions under which what was thought to be a law never holds, and where this can be shown repeatedly.
Compare Jules’s experiences with giving ladies foot massages. In Jules’s view, “Foot massages don’t mean shit.” Vincent continues:
VINCENT:
Have you ever given a foot massage?
JULES:
Don’t be tellin’ me about foot massages. I’m the fuckin’ foot master.
VINCENT:
Given a lot of ’em?
JULES:
Shit yeah. I got my technique down man, I don’t tickle or nothin’.
VINCENT:
Have you ever given a guy a foot massage?
JULES:
Fuck you.
Jules interprets his past experiences with foot massages to apply to
all
foot massages, and Vincent realizes that this isn’t so. It won’t be so whenever it is a man rather than a woman being given a foot massage.
As with Jules, sometimes our past experiences don’t tell us what will be the case in very different circumstances. For example, prior to 1919, let’s suppose, our experience with light did not suggest that gravity would bend it. In 1919, an experiment is done that indicates that the gravitational field of the sun bends the light of distant stars such that, during an eclipse, we can see the shift in the apparent position of the star. This test, actually performed in 1919, was taken to be an important step in confirming Einstein’s General Theory of Relativity, which predicted such a shift. It also helped overthrow some very long-standing views about the nature of our universe. But we don’t take our previous-to-1919 experience with light to undermine the claim that light can be bent by gravity because our previous experience with light did not involve viewing light as it passed through such a strong gravitational field. The testimony we have that light here on Earth does not appear to bend outside of a very strong gravitational field does not undermine the testimony that light bends as it passes through a very strong gravitational field. It’s not as if it were discovered that light sometimes bends in a strong gravitational field and sometimes does not, as would be the case with a miracle. Rather, it’s that light always bends in a gravitational field, and this can be shown repeatedly.
If someone does an experiment showing how Coke can be spontaneously turned into Pepsi, we can ask how the experiment was done and try it for ourselves as often as we like. With enough careful observation, we can, if needed, revise our understanding of the laws of nature to account for what we observe. There is not a lot we can do, however, to determine whether water was turned into wine by God two thousand years ago. There is no way to check repeatedly to see whether he really did, and asking him to do it again so we can check tends not to work. Hume’s point is not that it is impossible that miracles occur, but rather that the evidence against their occurrence is always going to be overwhelming.
Zed Is Dead
Sometimes it’s argued that if we have good reasons to believe that a god who performs miracles exists, then we shouldn’t be at all surprised when people report having seen one. Rather than thinking it’s unlikely that they are correct, we should expect that there is a good chance that they witnessed the real thing.
The problem here is that the appeal to miracles, all by itself, was supposed to be sufficient evidence to believe that a god exists. If we already need good reasons to believe that a god exists for the appeal to miracles to work, then we don’t need the appeal to miracles at all.
But what if two hundred atheistic scientists witnessed an apparently miraculous, non-repeatable event? Or you witness one yourself? Shouldn’t you then accept that a miracle has occurred?
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In a famous line, Hume says that a wise man “proportions his belief to the evidence.”
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So, I think Hume’s answer to these questions would be “No.” After all, what if, fifty years ago, two hundred atheistic scientists saw the Empire State building disappear? Then they would likely have thought it a miracle. Now we know it’s just David Copperfield. When our ability to collect or evaluate the evidence is very limited, it still seems more reasonable to withhold judgment as to whether a miracle occurred than to accept something that appears highly unlikely.
No doubt Jules was strongly affected by his experience. Perhaps it will even change his life. Is this evidence that it was a miracle? Well, whether it was a miracle or not does not seem relevant to the effect on Jules. His belief that it was a miracle is causing the change, and it would do so whether or not his belief is correct.
Hume, with characteristic wit, concluded his essay by writing that, “The Christian religion not only was at first attended with miracles, but even at this day cannot be believed by any reasonable person without one.”
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That’s a bold statement, but I think he was on to something.
12
Quentin Tarantino and the Ex-Convict’s Dilemma
RICHARD GREENE
A common occurrence in most Quentin Tarantino films is what has come to be known as a “Mexican standoff.” This refers to a situation in which two or more persons have weapons (usually firearms) pointed at one another, such that the persons are essentially paralyzed. They
can
act, but their doing so, no matter what they do, will likely result in either serious injury or death. I’m not going to use the term “Mexican standoff” in this chapter because (1) there is some question as to whether the term is racist in origin, and, more importantly for our purposes, (2) there may be a more apt description of the scenario as it appears in Tarantino’s films. Instead, I’ll use the term “ex-convict’s dilemma.”
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I’ll refer to any scenario involving an ex-convict’s dilemma as an “ECDS.”
In this chapter I’ll argue that the ex-convict’s dilemma is a special instance of what philosophers, economists, and decision theorists typically refer to as a “prisoner’s dilemma.” I’ll further argue that the most popular solution to the prisoner’s dilemma—the group rationality solution—cannot be applied to the ex-convict’s dilemma. This, of course, shows that the solution under consideration is lacking; a good general solution to a philosophical puzzle or paradox ought to be applicable to all or nearly all instances of the phenomenon. Tarantino’s frequent employment of the ex-convict’s dilemma is interesting in that he
manages (speaking very broadly) to show most or all of the different ways things can end up for a person who finds herself in just such a circumstance. While the results for persons in ex-convict dilemmas aren’t always catastrophic, they usually are. When things turn out well in these cases, there is usually quite a bit of luck involved. This will turn out to have interesting implications for the prospect of a rationality-based general solution to the prisoner’s dilemma.
The Prisoner’s Dilemma
So just what exactly is a prisoner’s dilemma? Suppose hypothetically that Ordell Robbie and Louis Gara (a couple of despicable hoods from
Jackie Brown
) have been arrested for fencing stolen goods and are being interrogated by the police. Ordell is in one interrogation room and Louis is in another. Suppose further that the police don’t have enough evidence to convict either of the more serious charge of fencing stolen goods, but have enough evidence to convict each of a less serious charge, such as possessing stolen stuff.
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The police make the following offer to each. “If you rat on your partner and your partner remains silent, then you will go free and your partner will go to jail for seven years. If neither you nor your partner rat on the other (in other words, if each stays silent), then you will both go to jail for one year (on the minor charge). If both partners rat on the other, then each will go to jail for four years.” Since both Ordell and Louis are in separate rooms, neither knows what the other one is doing. What should Ordell and Louis do?
The best thing from Ordell’s perspective is to rat on Louis and have Louis remain silent. Under that scenario, Ordell would do no jail time. The best thing for Louis, of course, is to have just the opposite happen. The problem is that if each goes for the optimal solution—no jail time—each ends up doing four years. They would be better off if neither spoke. Then each would get just one year. To this point it seems that perhaps the rational thing for each to do would be to remain silent, since if they don’t remain silent, they will both end up doing four years in the slammer as opposed to one year.
Unfortunately, matters are not quite so simple. Notice that no matter what Ordell does, Louis is better off if he rats on Ordell. Consider the case in which Ordell remains silent. If Ordell doesn’t rat and Louis does, then Louis goes free. If Ordell stays silent and Louis doesn’t rat either, then each gets one year. So if Ordell stays silent, Louis should rat (assuming he’s going only by his own self-interest).
Now consider the case in which Ordell rats on Louis. If both Ordell and Louis rat, then each gets four years. If Ordell rats and Louis doesn’t, then Louis gets seven years. So if Ordell rats, Louis should too. So regardless of what Ordell does, Louis should rat on Ordell. The same holds for Ordell—he should rat regardless of what Louis does. Given this line of reasoning it seems like the rational thing for each to do is to rat on the other. But, again, if each does the rational thing, then each gets four years in the pokey and is worse off than if each had remained silent. The result of all this is a paradox—rationality is typically cashed out in terms of behavior that maximizes self-interest, but rational behavior in this case results in the persons involved being worse off than had they not done the rational thing.
The Prisoner’s Dilemma—Not Just for Prisoners Anymore
The term “prisoner’s dilemma” is applicable to any number of situations, provided that the situation has the essential elements described above—that persons behaving “rationally” leads to everyone being worse off, and, paradoxically, that no matter what others do, one is better off doing the “rational” thing. It’s not essential that a prisoner’s dilemma involve only two decision makers (although there must be at least two), nor is it essential that a prisoner’s dilemma actually involve prisoners.
While the term “prisoner’s dilemma” was formulated only recently (in the 1950s by folks at the RAND Corporation), prisoner’s-dilemma scenarios have played key roles in philosophical arguments for centuries. Perhaps the most famous instance of a prisoner’s dilemma scenario occurs in Plato’s
Republic
. The character Glaucon argues that the origin and nature of justice involves a situation where persons in a state of nature improve their lot by agreeing
not
to behave in rational and self-interested ways. The result is a contract state in which everyone (or almost
everyone) is better off than they would be in the state of nature. William Forster Lloyd’s
Tragedy of the Commons
is also an instance of the prisoner’s dilemma (if everyone fully exploits commonly owned resources for their own individual benefit, the result is the over-exploitation of those resources, and every individual is worse off). Even certain day-to-day situations, such as traffic jam scenarios, can have the essential elements of a prisoner’s dilemma.
Notice that the ex-convict’s dilemma has the essential elements of a prisoner’s dilemma, and thus is an instance of the prisoner’s dilemma. Consider the first of two ECDS’s that Tarantino treats his audience to in
Reservoir Dogs
. Two criminals, known only to each other by their codenames—Mr. White (Harvey Keitel) and Mr. Pink (Steve Buscemi)—have just been involved in a failed robbery attempt. To say things have gone terribly wrong would be a huge understatement. They are at the rendezvous point, which is an empty warehouse, along with an incapacitated Mr. Orange (Tim Roth). As tempers flare, they scuffle and eventually wind up in very close proximity with handguns pointed directly at each other’s faces. As in a prisoner’s dilemma scenario they have two actions available to them: lower their handgun or do nothing for the moment. If they both lower their guns, they both survive. If Pink lowers his gun but White does not, Pink could be shot and White can accomplish whatever goal he had hoped to accomplish by pointing his gun at Pink in the first place (in this particular case White desires to take Orange to a hospital against the protestations of Pink). Similarly, if White lowers his gun and Pink does not, then White could die and Pink would be able to accomplish his goal (Pink is trying to get White not to take Orange to the hospital, as doing so might endanger the group). Finally, if neither lowers their weapon, then both may well end up seriously injured or dead. In such cases people tend to become more rash or panicky as time goes on. Hence the likelihood of both persons being shot increases with each passing moment, although the greater likelihood is that the person who shoots second will end up in worse shape than the person who shoots first (being shot at tends to mess up one’s aim and concentration).
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