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The Doctrine of Double Effect

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Description | Example | Discussion | So what?

Description

The 'Doctrine of Double Effect' is a philosophical position that suggests that a good action that has a bad side-effect is morally permissible. It may even be seen as good, provided the harm was not intended. The doctrine holds also if the potential side effect was understood.

Controls on the doctrine include:

• The intent of the person should be to do good (helping others, not just oneself).
• The action should be morally good.
• The action should be highly likely to cause the good result.
• There should no better alternative.
• The bad result should be a side-effect to the good result.
• The action should be proportional and minimal to achieve its good result, thereby minimizing the bad side-effect.

Example

A doctor gives pain-relieving drugs to a terminal patient, even though she knows the drug may shorten the person's life.

A soldier whose weapon has jammed throws a grenade that kills several people, including one of his own men, yet the action stops a deadly enemy advance.

Discussion

This doctrine is often used in medicine, where relief from extreme pain is more urgently felt than prolonging life where happiness would be very low. It is still a difficult decision and other factors such as the level of pain and wishes of the patient and the family need to be taken into account.

It can be difficult to take any decision about life and death and can be affected by personal morals and religion. Such dilemmas can also cause hesitation that may lead to greater harm than the side-effect alone. Inaction is a decision that can lead to much later regret.

When thinking about hard decisions, people may seek to justify their actions and take the 'best worst' choice. In particular they may well consider personal social consequences and how they may be blamed for that they did. Having reason, even when it is dire, is often far better than just reacting (although in sudden events we do just this and then seek post-justification).

A danger is that people who have evil intent use this doctrine to justify their actions, even though they are not following the principles when harm to others or selfish gain is a primary purpose of their actions.

This doctrine is attributed to Thomas Aquinas in is Summa Theologica.

So what?

When you have difficult choices, carefully consider both the potential good and bad effects of your options.

See also

The Seven Deadly Sins

Aquinas, Thomas (13th c). Summa Theologica II-II, Q. 64, art. 7, “Of Killing”, in On Law, Morality, and Politics, William P. Baumgarth and Richard J. Regan, S.J. (eds.), Indianapolis/Cambridge: Hackett Publishing Co., 1988, pp. 226–7