An explanation of this ethical doctrine, which suggests that when an action will have two consequences (a "double effect"), the ethicality of that action depends on which of the effects was intended.
An explanation of this ethical doctrine, which suggests that when an action will have two consequences (a "double effect"), the ethicality of that action depends on which of the effects was intended.
This doctrine says that if doing something morally good has a morally bad side-effect, it's ethically OK to do it providing the bad side-effect wasn't intended. This is true even if you foresaw that the bad effect would probably happen.
This might seem counter-intuitive, but the principle is used in serious argument about some important issues in ethics.
Although euthanasia is illegal in the UK, doctors are allowed to administer potentially lethal doses of painkilling drugs to relieve suffering, provided they do not primarily intend to kill the patient. This is known as the doctrine of double effect.
BBC News, November 2000
This principle is commonly referred to in cases of euthanasia. It is used to justify the case where a doctor gives drugs to a patient to relieve distressing symptoms even though he knows doing this may shorten the patient's life.
This is because the doctor is not aiming directly at killing the patient - the bad result of the patient's death is a side-effect of the good result of reducing the patient's pain.
Many doctors use this doctrine to justify the use of high doses of drugs such as morphine for the purpose of relieving suffering in terminally-ill patients even though they know the drugs are likely to cause the patient to die sooner.
This is not a blanket justification. The doctor's action must still be appropriate: more on what factors are needed to use the doctrine of double effect as a defence for euthanasia.
In modern warfare it's difficult to ensure that only soldiers get hurt. Despite the effectiveness of precision weapons, civilians are often hurt and killed.
The doctrine of double effect is sometimes put forward as a defence, but it does not always apply.
For example, if an army base in the middle of a city is bombed and a few civilians living nearby are killed as well, nothing unethical has been done, because the army base was a legitimate target and the death of civilians was not the intention of the bombing (even though their death could be predicted).
The doctrine of double effect can't be used to defend the use of weapons of mass destruction, such as non-precision nuclear weapons, area bombing, or chemical or biological weapons used against a population in general, since these are so indiscriminate in effect that civilian casualties can't be regarded as a secondary result.
In cases when saving the life of a pregnant woman causes the death of her unborn child - for example, performing an abortion when continuing the pregnancy would risk killing the mother - some people argue that this is a case of the doctrine of double effect.
By this argument, the death of the foetus is merely the side-effect of medical treatment to save the mother's life.
Other people take the more traditional view that this is a case of self-defence against a threat (albeit a threat that is innocent and unaware that it is a threat).
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