A proximate cause is an event which is closest to, or immediately responsible for causing, some observed result. This exists in contrast to a higher-level ultimate cause (or distal cause) which is usually thought of as the "real" reason something occurred.
- Example: Why did the ship sink?
- Proximate cause: Because it was holed beneath the waterline, water entered the hull and the ship became denser than the water which supported it, so it could not stay afloat.
- Ultimate cause: Because the ship hit a rock which tore open the hole in the ship's hull.
In most situations, an ultimate cause may itself be a proximate cause for a further ultimate cause. Hence we can continue the above example as follows:
- Example: Why did the ship hit the rock?
- Proximate cause: Because the ship failed to change course to avoid it.
- Ultimate cause: Because the ship was under autopilot and the autopilot's data was inaccurate.
- (even stronger): Because the shipwrights made mistakes in the ship's construction.
- (stronger yet): Because the scheduling of labor at the shipyard allows for very little rest.
- (in absurdum): Because the shipyard's owners have very small profit margins in an ever-shrinking market.
Separating proximate from ultimate causation frequently leads to better understandings of the events and systems concerned.
In ordinary affairs
In ordinary affairs as well as in science, engineering, and other fields, all of the characteristics of an effect will be completely explained by the set of proximate causes. If a postulated (hypothesized) set of proximate causes (also known as "direct factors") does not fully explain all of the characteristics (attributes) of the effect, then the set of direct factors is either wrong or incomplete.
The set of direct factors (of an effect) has a number of known properties:
- Predisposing factors that set the stage for the effect and a precipitating factor that brought the effect into being. (The future recurrence of the effect may be precluded by negating certain predisposing factors and/or by negating the precipitating factor. For example, the detonation of a car bomb could be precluded by removing the bomb or by not turning the ignition key.)
- These factors may be considered to be predisposing factors:
- The nature of the effect
- The magnitude (or intensity) of the effect
- The location of the effect
- May be considered to be precipitating:
- The timing of the effect.
- The vulnerability for the effect
- the creation of the effect
- The factor(s) that made the effect as large [intense] as it was
- The factor(s) that kept the magnitude [intensity] from being even greater.
The set of direct factors will always include:
- Something that can be affected
- Something that can do the affecting
- The proximity of the foregoing
- The simultaneity of the first two
- The absence of any intervening separation between the first two. (This is the paradigm of "barrier analysis.")
- Ultimate causation explains traits in terms of evolutionary forces acting on them.
- Example: female animals often display preferences among male display traits, such as song. An ultimate explanation based on sexual selection states that females who display preferences have more vigorous or more attractive male offspring.
- Proximate causation explains biological function in terms of immediate physiological or environmental factors.
- Example: a female animal chooses to mate with a particular male during a mate choice trial. A possible proximate explanation states that one male produced a more intense signal, leading to elevated hormone levels in the female producing copulatory behaviour.
Although the behavior in these two examples is the same, the explanations are based on different sets of factors incorporating evolutionary versus physiological factors.
These can be further divided, for example proximate causes may be given in terms of local muscle movements or in terms of developmental biology (see Tinbergen's four questions).
In analytic philosophy, notions of cause adequacy are employed in the causal model. In order to explain the genuine cause of an effect, one would have to satisfy adequacy conditions, which include, among others, the ability to distinguish between:
- Genuine causal relationships and accidents.
- Causes and effects.
- Causes and effects from a common cause.
One famous example of the importance of this is the Duhem-Quine thesis, which demonstrates that it is impossible to test a hypothesis in isolation, because an empirical test of the hypothesis requires one or more background assumptions. One way to solve this issue is to employ contrastive explanations. Several philosophers of science such as Lipton argue that contrastive explanations are able to detect genuine causes. An example of a contrastive explanation is a cohort study that includes a control group, where one can determine the cause from observing two otherwise identical samples. This view also circumvents the problem of infinite regression of 'why's that proximate causes create.
Sociologists use the related pair of terms "proximal causation" and "distal causation."
Proximal causation: explanation of human social behaviour by considering the immediate factors, such as symbolic interaction, understanding (Verstehen), and individual milieu that influence that behaviour. Most sociologists recognize that proximal causality is the first type of power humans experience; however, while factors such as family relationships may initially be meaningful, they are not as permanent, underlying, or determining as other factors such as institutions and social networks (Naiman 2008: 5).
Distal causation: explanation of human social behaviour by considering the larger context in which individuals carry out their actions. Proponents of the distal view of power argue that power operates at a more abstract level in the society as a whole (e.g. between economic classes) and that "all of us are affected by both types of power throughout our lives" (ibid). Thus, while individuals occupy roles and statuses relative to each other, it is the social structure and institutions in which these exist that are the ultimate cause of behaviour. A human biography can only be told in relation to the social structure, yet it also must be told in relation to unique individual experiences in order to reveal a complete picture (Mills 1959).
- Gray, P. (2007) Psychology (5th Ed.) (pp. 64-66) New York: Worth Publishers
- Greenberg, G. (1998) Comparative Psychology: A Handbook. US: Taylor & Francis. pp. 666
- Mayr, E. (1988). Toward a new philosophy of biology: Observations of an evolutionist. Cambridge, Massachusetts: Harvard University Press.
- Mills, C.W. ( 2000). The Sociological Imagination. 40th ed. New York: Oxford University Press.
- Naiman, J. (2008). How Societies Work: Class, Power and Change in a Canadian Context. 4th ed. Halifax and Winnipeg: Fernwood Publishing.
- Thierry, B. (2005, October 10). Integrating proximate and ultimate causation: Just one more go!, Current Science, Vol. 89 (7), 1180-1184.
- Lipton, Peter (1990). Contrastive Explanation. Royal Institute of Philosophy Supplement 27:247-266.