This certainly explains why the radiator of this car burst; such things always happen when a radiator full of water without antifreeze is exposed to subfreezing weather. Scientific explanations are also predictions: “why?” also means “on what occasions?” But is this a historical explanation? A historian would want to go well beyond it; for him the real question would be why the owner exposed the car in this manner. Was he unaware of what happens to unprotected cars in such temperatures? Unlikely. Did he, wrongly, think that he had put antifreeze in the car? Or was he misled by a faulty weather forecast?
Questions like these made historians disinclined to accept this as an example of a satisfactory historical explanation. The author of the example, the philosopher Carl Hempel, granted as much. As he understood, historians do not explain but give “explanation sketches” that have to be filled out before they attain that dignity. One prodigious difficulty is that no covering laws of history have been discovered. One candidate for such a law is, “Whenever two armies, one much larger than the other but equally well led, meet in battle, the larger one always prevails.” The difficulty with this is that there are no independent standards for evaluating leadership. There are examples of much smaller armies beating larger ones, and one counterexample is enough to disconfirm a law. If one tries to save the law by saying that, in those cases, the armies were not equally well led, the argument becomes circular. Another candidate for a historical law is, “Full employment and stable prices cannot exist at the same time.” Some would argue that these supposedly incompatible conditions were achieved in the U.S. economy in 1997. It all depends on how full employment is defined. It is an additional complication that this law, if it is a law, may be restricted in its application to capitalism.
For many years the lack of well-warranted covering laws seemed to be the chief difficulty with this conception of historical explanation, but chaos theory has recently raised another problem: the boundary conditions cannot be exactly specified. Even a minute and imperceptible variation in the original state of a system may have large and entirely unpredictable consequences at some time in its future state. (This is picturesquely dramatized in the image of a butterfly sneezing in Africa and the ensuing hurricane in Florida.)
Hempel subsequently modified his position by substituting high probabilities for invariable laws. In other words, an event might be explained by showing that, under these conditions, the outcome was what usually or almost always happened. This maneuver gave up the ideal of the unity of scientific explanation—that explanation in history would have the same logical structure as that in physics—because showing what almost always happens does not explain why, for this particular event, the outcome was the more- rather than the less-usual one. On the other hand, many generalizations in history have a high degree of probability but are not certain—including the likely result of going into battle with far inferior forces. It is also highly useful to know whether outcomes were almost certainly going to occur or whether they were complete surprises. And it is worthwhile trying to discover more such generalizations.
Such generalizations in fact play an important part in the other principal account of historical explanation, which focuses on the reasoning processes and intentions of historical actors. This approach is more congenial to historians than the one that attempts to work with historical laws, and it has been formulated by philosophers who were either historians themselves (R.G. Collingwood) or particularly acquainted with historical work (William Dray and Louis Mink). Its classic statement, by Collingwood, was that the historian’s “why?” is not “on what occasions?” but “what did he think, that made him do it?” Collingwood believed that the historian could rethink the thoughts of the actor (as one can work out the same geometrical reasoning as Pythagoras); thus, historical knowledge could be based on a kind of acquaintance. Although Collingwood did not discount the presence of irrational elements in historical action, other historians put more emphasis on understanding these elements through empathy or intuition.
It is difficult for explanations of this kind to avoid a kind of circularity. People deliberating on an action usually have reasons to do more than one thing, and they are very seldom in the habit of leaving a written record of their deliberations. Consequently, the historian almost always has to work backward, from what was done to the reasons for doing it. But the evidence that these were the reasons for doing it is that it was done. So what is supposed to explain an action is instead explained by it. The “logic of the situation”—showing that, under the circumstances, what was done was the right or reasonable thing to do—is commonly advanced as an explanation by historians, and it can undoubtedly be convincing if one is not too fussy about what constitutes an explanation. But this means that the explanation is plausible or persuasive, not logically compelling—in other words, it signals a shift toward rhetoric.
Most of what philosophers and historians have thought about explanation has centred on how to explain single events or actions. History, however, is about far more than these, and historical writing in the 20th century moved steadily away from emphasizing individual action and toward the history of large-scale social structures. Furthermore, history is not composed of well-thought-out actions that accomplish their goals; it is instead full of the unintended consequences of actions. These result from social processes that obviously were not anticipated or understood by the actor. While the existence of unintended outcomes obviously poses insuperable difficulties for explanations in terms of individual intentions, it is exactly what theories of universal history are equipped to explain. The first articulation of the providential theory, Genesis 50:20, shows that Joseph’s envious brothers had inadvertently performed God’s will when they sold him into slavery, since he rose to high office in Egypt, managed the food supply so as to avert famine, and so had food to give his brothers. As Joseph says to them, “You meant evil against me; but God meant it for good, to bring it about that many people should be kept alive.”
In a similar vein, Vico’s “rational civil theology” recognizes that “men have themselves made this world of nations” but goes on to assert that “this world without doubt has issued from a mind often diverse, at times quite contrary, and always superior to the particular ends that men had proposed to themselves, which narrow ends, made means to serve wider ends, it has always employed to preserve the human race upon this earth.” Intending just to gratify lust, humans create the institution of marriage; intending to exert power over others, they wind up with civil laws.
Much the same argument can be found in Adam Smith’s notion of the invisible hand, which produces for society the optimum distribution of goods even though homo economicus acts totally selfishly. Hegel’s great men, or world-historical individuals, such as Alexander the Great and Napoleon, are similarly moved only by ambition, but the result of their actions furthers the development of Spirit in spreading Greek culture and a rational code of law. Hegel calls this the “cunning of Reason.” Finally, for Marx, individual capitalists, and the bourgeoisie as a class, act only to increase their power and perpetuate their profits, but the result of their actions is inevitably to increase the number and misery of the proletarians who will eventually overthrow them.
Theories like this necessarily suggest that history is being made behind the backs (or over the heads) of actual humans, since they cannot “make history” by achieving the goals of their actions. It appears that some sort of commitment of faith is required to accept one of these master narratives. God, or a cosmic teleology, is the ultimate explanation of everything, which means that there is nothing that cannot be explained in those terms. Logicians, however, say that universal explanations are vacuous, since nothing could happen that would show that the explanatory principle was inapplicable.