Elizabeth Anscombe starts her essay ‘Causality and Determination’ by noting the two ways in which causality is usually defined:
- Necessary connection
- An exceptionless generalisation: an event always follows based on certain antecedents
The first definition (necessary connection) is based on Hume’s second definition of cause and effect. Although Hume doesn’t refer to ‘necessary connection’ specifically, he describes cause as the process via which ‘the idea of one object causes the mind to form the idea of the other’. This reinforces Hume’s notion that necessary connection is a process that occurs in the mind.
The second definition (exceptionless generalisation) is based on Hume’s first definition of cause and effect. All events resembling event c (cause) must be followed by events resembling event e (effect).
Both definitions give rise to an assumption: if cause A results in effect B in one case, but cause A does not result in effect B in another case, there must be a further cause. This idea is captured by Hume’s Rule 6 on Section 15 (refer to post 0074).
To support her argument that these views have become entrenched in philosophy, Anscombe refers to a number of former philosophers and how they supported some variety of ‘necessary connection’:
- Aristotle: although Aristotle speaks of ‘necessity’, this may not have the same meaning in comparison to Hume. For Aristotle, necessity occurs when the agent has the power to act, which only happens when the agent has the desire.
- Spinoza: Spinoza also presents a similar definition: given a cause, an effect follows of necessity. If there is no cause, then no effect will result.
- Hobbes: You cannot understand the effect without understanding the cause. Anscombe notes that Hobbes’ view sets up a logical connection between cause and effect
Anscombe agrees with Hume in that the Hobbes view is incorrect. Cause and effect can never be a logical relationship. Rather, Hume relied on the idea of ‘necessary connection’, an impression of the mind based on experiencing constant conjunctions between two events, as opposed to some inherent property that exists in the objects. Although Hume’s argument is not based on logic (the necessary connection instead comes about from experience), the argument does suggest that necessary connection gives rise to a set of deterministic laws.
Hume stresses in Section 2 that three requirements should be present for cause and effect: (1) contiguity, (2) priority in time (the cause must happen prior to the effect), and (3) necessary connection. In terms of (3), Hume asserts this exists, rather than providing evidence.
Philosophers after Hume have merely re-enforced the idea of necessity in defining cause and effect. Kant agreed with Hume in that the effect must ‘invariably and necessarily’ follow from the cause. John Stuart Mill also indicated that causation had to be based on ‘necessary’ and ‘sufficient’ conditions.
Bertrand Russell however did provide an objection to the standard point-of-view, even if he didn’t offer any alternative theory of causality. Russell suggested that necessity only works if we can introduce the concept of universality, and it is far from certain if this can ever be proven.
Anscombe’s argument against Hume and the other classical philosophers revolves around the fact that cause and effect does not work in the proposed way when we consider real life examples. Anscombe uses the case of a person being in contact with someone who has a contagious disease. If you then go and see the doctor, he/she will respond along the lines of ‘you may or may not get the disease’. So this suggests that the effect (catching a contagious disease yourself) does not NECESSARILY follow because of the cause (contact with a diseased person).
In response to this, a critic might argue that the cause is too ill-defined and unclear in cases such as this. Catching the disease isn’t just a case of mere contact, but of some other underlying condition. In other words, doctors do not know everything about disease.
Anscombe dismisses this argument. Firstly, the critic is assuming that there has to be some extra cause that is currently unknown, but this is just speculation not based on any facts. Maybe there is nothing further for us to know? How do we know that there is something else that needs to be discovered?
Secondly, even if the critic is correct (further information is needed to explain the cause), this doesn’t change the fact that being in physical contact with someone is a genuine state that causes someone to catch a disease. The cause cannot be denied from the observable effect.
Anscombe also points out that knowledge of causes does not mean we have to know exactly WHY the causes result in the effects they do. Consider the examples of creating fire by rubbing two sticks together. This does not rely on the person knowing what it is about the process that causes the fire to form. In addition, when we have knowledge of causes, we are not interested in seeking clarity of ‘valency’ or ‘long-run frequency’, that is, statistical proof that the cause always brings about the effect as a universal law of nature. We do not need to run a scientific experiment to convince ourselves of the notion that fire is created by rubbing two sticks together.
Having considered the traditional view of causality, Anscombe will next provide her own interpretation on how we should perceive cause-and-effect.