PHIL 5973: Mental Causation Seminar University of Arkansas, Fall 2003 Topic: Causation Background This course covers the topic of mental causation. While we will have many readings dealing with mentality, we will have none dealing with causation in a general sense. However, many of the authors we will read explicitly rely on one of the standard analyses of causation (e.g., Davidson, Fodor, and Kim accept a “nomological” analysis; Lewis, LePore, Loewer, and Yablo a “counterfactual” analysis). The main goal of this opening class is to present, at a level of great generality, the most popular approaches to analyzing the concept of causation, and raise general worries for each of them. (I stress, this is a very brief and incomplete presentation of the topic.) An analysis of causation will fill in the blank of the following claim: a caused b if, and only if, _______. 1. Humean, regularity, or “nomological” analyses The general form of analysis on these views is: a caused b if, and only if, i) a and b occurred, ii) a falls under type j and b falls under type k ,and iii) it is a law that k-type events follow jtype events. For example: The executioner’s injection of drug X into the convict’s arm caused him to die. Why? ‘The executioner’s injection of drug X into the convict’s arm’ falls under the type ‘poisoning by drug X’ and the convict’s death falls under the type ‘death’, and it is a law that deaths follow drug X poisonings. *Note: a) In this analysis, iii) informs us that causes precede their effects. In those to follow, no such requirement is given specifying that a must precede b. b) ‘a’ and ‘b’ stand for particulars—event or property tokens. We should be careful to distinguish singular causal judgments from general (type-level) causal judgments. The Humean explains the former in terms of the latter. Objections: a) What is a law? And is this understanding of a law appropriate for backing causation? A developed Humean analysis of causation will have to provide standards for lawhood. One standard might be: It is a law that k-type events follow j-type events if, and only if, all observed j-type events have been followed by k-type events. But, one might object, this standard is both too weak and too strong. It might be too weak in that not enough observations have been made, the correlation could be coincidental, or k-type events might be the result of a common cause, etc. The standard might be too strong in that there seem to be laws with exceptions that nevertheless back causal claims. These are ceteris paribus laws. Most, if not all, psychological “laws” are of this type, but many (Fodor, for one) think such laws are sufficient to back causal claims. Eric Funkhouser 1 8/26/03 Coming up with appropriate standards for lawhood is tough, and Humean analyses of causation might just be moving the bulge in the carpet to this area. b) This analysis doesn’t distinguish real causation from epiphenomenal causation, or cases of common causes. There are some cases in which, though k-type events reliably follow j-type events, our intuitions are that j-type events do not (or at least might not) cause k-type events. In part, this may be because some i-type event is responsible for both the j-type and k-type events. If the i-event is simultaneous with the j-event, we have a case of epiphenomenal causation. If the i-event precedes the j-event, we have a “common cause” case. Examples: Epiphenomenal Causation: My dog has been trained so that it reliably sits whenever I issue the command “Sit!”. There is a law-like connection between my uttering words that mean sit and her sitting behavior, and there is no such connection with words with different meanings (e.g., ‘come’, ‘stay’, etc.). But, one might think that the meaning of the word ‘sit’ nevertheless is causally irrelevant to her behavior. My dog doesn’t sit because of the meaning of the word ‘sit’, but because of the mere sound of the word and its association with rewards. (Maybe dogs do understand content, though. Then we should give an example for a “dumber” animal.) Common Causes: It has been observed that a certain symptom (say, a peculiar type of rash) is always followed by illness X. Because of this law-like connection, one concludes that the rash causes illness X. Actually, this is mistaken. What happens is a virus is present, which causes two different effects: the rash and the illness. Because the rash occurs before the illness, there is the appearance that the rash causes the illness. In fact, there is no causal connection between the rash itself and the illness (e.g., one could acquire the rash, and that would not cause one to then contract the illness). c) There seem to be cases of real causation, absent regularities. Example: Shaq breaks his foot in April, and the Lakers lose him for the playoffs. The Lakers end up losing in the second-round. It is plausible that Shaq’s broken foot caused the Laker’s to lose so early in the playoffs. However, there is no regularity between Shaq’s broken feet and early playoff exits. d) Humean analyses emphasize the sufficiency aspect of causation, but causes must also be necessary (in the circumstances) for their effects. Plus, causes needn’t be strictly sufficient for their effects. Causes needn’t be strictly sufficient, because it certainly seems true that match-strikings can cause fires (though they’re not strictly sufficient for fires). Eric Funkhouser 2 8/26/03 Conversely, something might be strictly sufficient for an outcome, though not cause it. Maybe the initial conditions of the Big Bang were sufficient for our being in this classroom today. But those precise details might be at the wrong level of abstraction to explain the macro-phenomena of our being here-now. *Because of these kinds of worries, John Mackie famously introduced his INUS conditions for causation. Humeans of interest (for the purposes of this class): David Hume, Donald Davidson, Jerry Fodor, and Jaegwon Kim 2. Probabilistic causation The general form of analysis on these views is: a caused b if, and only if, i) a and b occurred and ii) a’s occurrence raised the probability that b (as compared to a’s non-occurrence). *This form of analysis can be given a more technical, mathematical formulation in terms of conditional probability. Typically, many other bells and whistles are added in an attempt to avoid some of the objections considered below. One main motivation for this view is that it captures statistical generalizations that back many causal claims. For example, lung cancer doesn’t invariably follow from a life of cigarette smoking. But there is a statistical correlation strong enough to back the claim that cigarette smoking causes lung cancer. The probabilistic analysis captures this judgment, and it is not clear that the standard Humean view captures it as well (though developments in this tradition—e.g., by J.S. Mill, Mackie, etc.—offer substantial improvements). Obviously, a probabilistic analysis is also better suited at capturing indeterministic causal relations. This is a point in favor of probabilistic analyses if our world is, in fact, indeterministic (as quantum mechanics suggests). Objections: a) Probability raising is symmetric, but causation is asymmetric. This analysis does not distinguish cause from effect. b) This analysis succumbs to the same worry about epiphenomenalism that besets the Humean version. c) Sometimes causes actually decrease the likelihood of their effects. Example: Katie doesn’t want to study for her philosophy exam, so she goes out to the bar instead. While drinking at the bar, she runs into someone who took the same exam last year. Katie makes arrangements to get a copy of this person’s exam and memorizes the answers just before her exam. Katie receives an ‘A.’ It seems that Katie’s going to the bar and not studying that night was a cause of her earning an ‘A’ on the philosophy exam. But it certainly doesn’t seem that going to the bar and not studying for an exam increases the likelihood of receiving an ‘A.’ Eric Funkhouser 3 8/26/03 *It should be obvious that depending upon how the causal-candidate is described, the probability judgments will differ. E.g., ‘going to the bar and running into someone who took the exam the year before’ might increase the probability of earning an ‘A’. d) Conversely, sometimes events increase the likelihood of an outcome without causing it. Example: Katie stays at home and studies for her philosophy exam to the best of her ability. Unfortunately, she focused on the wrong material. During the exam, Katie panics—the material is not at all what she expected. Out of desperation, she shamelessly cheats off of the star pupil beside her. Katie receives an ‘A’. Though studying for the philosophy exam to the best of her ability does increase the chances of Katie receiving an ‘A’, it seems clear that this studying did not cause her to receive an ‘A’. Instead, her cheating caused her to receive an ‘A’. e) Because of these worries, one might think that probabilistic analyses are appropriate for general (type-level) causal claims, but not for singular causal claims. Probability theorists of interest: Hans Reichenbach, Christopher Hitchcock, Ellery Eells, Patrick Suppes, and Nancy Cartwright 3. Counterfactual analyses The general form of analysis on these views is: a caused b if, and only if, i) a and b occurred and ii) b would not have occurred if a had not occurred. Objections: a) How are the counterfactuals evaluated? A common worry about counterfactuals concerns their capacity for being evaluated as true or false. What kind of “fact” is a true counterfactual statement? How can we know how the world would have been had such-and-such, when such-and-such didn’t occur? We can easily see why Empiricists have traditionally been uneasy with counterfactual statements, since no examination of the world can verify them directly. Still, in everyday speech we accept counterfactual statements frequently (or at least argue about them in a way that takes them as truth-evaluable). E.g., Bobby Kennedy would have won the Democratic Party nomination in 1968, had he not been assassinated. The U.S. Olympic basketball team wouldn’t have lost to the U.S.S.R. in 1972 had NBA (and ABA!) players been allowed to play. Starting in the 1960’s, however, David Lewis developed a possible-worlds theory for evaluating the truth of counterfactuals. In order to determine if b would have occurred had not-a, we must “look” to the “nearest possible world” in which not-a and “see” whether b. There are obvious difficulties with this proposal. Of course, we cannot observe these worlds in any traditional sense (e.g., with our 5 senses). And how do we know what counts as the Eric Funkhouser 4 8/26/03 “nearest possible world”? Two factors must be balanced in making such determinations: qualitative resemblance and fidelity to the laws of the actual world. b) Cases of causal pre-emption and overdetermination are counter-examples to a simple counterfactual analysis. Pre-emption example: One way or another, John is going to be told the bad news. His two friends, Jack and James, know that one of them has to tell John. Jack breaks the news to John, and John breaks down and cries. But if Jack hadn’t told John the news, James would have. It seems clear that ‘Jack telling John the bad news’ caused ‘John’s breakdown.’ But, this does not follow from a simple counterfactual analysis of causation. For, in the “nearest possible world” in which Jack doesn’t tell John the bad news, James tells the news instead. In such a case, John still breaks down and cries. Overdetermination example: A convict before a firing squad is struck in the heart, simultaneously, by the bullets of two sharpshooters. The convict dies. Did either, or both, of the sharpshooters kill (i.e., cause the death of) the convict? The convict’s death, it seems, does not counterfactually depend on either pulling the trigger/shooting the convict. For example, in the “nearest possible world” in which shooter A either doesn’t pull the trigger or fails to hit his target, the convict still dies because shooter B performs that task (as B does in the actual world). So, A’s pulling the trigger/hitting his target didn’t cause the convict’s death. For parallel reasons, B’s pulling the trigger/hitting his target didn’t cause the convict’s death either. But, didn’t they each cause his death? (I.e., Wasn’t his death overdetermined?) One available response is to say that they jointly caused this death, and the effect would have been different had only one of them struck their target. But, doesn’t it sometimes happen that the effect is the very same regardless if one or two possible causes run their course? Counterfactual theorists of interest (for the purposes of this class): David Lewis, Ernie LePore, Barry Loewer, and Stephen Yablo 4. Primitivism According to the Primitivist, causation is unanalyzable. There are certain concepts that are fundamental and are not to be analyzed in more basic terms. Objection: a) This just gives up the game. We could always go primitivist about any concept, but we should try to find an analysis if possible. And the connections between causation and both laws and counterfactuals seem especially promising routes to explore. Primitivists of interest: G.E.M. Anscombe, David Armstrong, and Michael Tooley Eric Funkhouser 5 8/26/03