Is there a word for something that is immoral or unethical, but must be done since it is beneficial. For example you would use the word to describe something like this, "we must kill those who misbehave so that we may maintain peace and prosperity in the country". Or another good example is Dexter from the TV show Dexter, he kills people, but he kills them because they are bad people.
This is called a necessary evil (also known as the lesser of two evils). It is used to refer to a choice that is bad, but preferable to the alternative choice that is much worse.
In your example, you have 2 choices:
- Kill people who are violent criminals.
- Do not kill those violent criminals and allow them to continue to harm society.
Killing violent criminals could be considered immoral, but it can be considered a necessary evil since the alternative of letting them live and continue to harm society is worse.
There are even a lot of references on the Internet to Dexter as a "necessary evil".
A term worth considering is utilitarian (Merriam Webster)
- of or relating to or advocating utilitarianism
where utilitarianism is (wikipedia)
a theory in normative ethics holding that the proper course of action is the one that maximizes utility, usually defined as maximizing total benefit and reducing suffering or the negatives.
In other words, utilitarianism is balancing the benefits against any negative associations and acting accordingly (the benefits outweigh the moral costs).
You could also consider immoralistic (Wiktionary)
related to immoralism or an advocate of immoralism
where immoralism is (Wiktionary)
A philosophy that does not accept moral principles
The term comes up in discussions of Plato's The Republic, where the primary topic is justice and its benefits, but includes arguments on defining morality as well. Thrasymachus argues that true justice and ethics is actually contrary to the principles of justice and morality that others hold, saying they are what is in the interest of the stronger.
Sparks Notes provides this in its analysis:
As Thrasymachus makes clear, justice is not universally assumed to be beneficial. For as long as there has been ethical thought, there have been immoralists, people who think that it is better to look out for your own interest than to follow rules of right and wrong.
Based on this, you might give thought to the formation Thrasymachian to describe the concept submitted by Thrasymachus, as summarized by that last sentence.
An immoralistic or Thrasymachian attitude is a selfish one, and it assumes the actor is superior to others and entitled to look after their self-interest before the interest of others.
Machiavellian: (from TFD)
or pertaining to Machiavelli. - being or acting in accordance with the principles of government analyzed in Machiavelli's The Prince, in which political expediency is placed above morality.
- Scholars often note that Machiavelli glorifies instrumentality in statebuilding—an approach embodied by the saying that "the ends justify the means." Violence may be necessary for the successful stabilization of power and introduction of new legal institutions. ( from Wikipedia)
Opportunistic may also convey the meaning you are describing:
- opportunistic - taking immediate advantage, often unethically, of any circumstance of possible benefit.
For the common good
It's not a single word because as Erik Kowal rightly says, the concept of doing something immoral or unpleasant which ends up being beneficial for the entire community, is a complex one. Usually society (or our parents) tells us to perform good deeds and acts of kindness, there is the idea of cultivating "positive behaviour" among members within the same society. Sometimes we call these acts altruism. But in the OP's example, some might argue that murdering people, is not altruistic but immoral. The fact that these people who deserve to die may be "evil" or "bad" does not justify the action in itself.
However, the counter argument that one meets up against is that these acts are for the common good.
In philosophy, ethics, and political science the common good or common weal is a specific "good" that is shared and beneficial for all or most members of a given community.
The good that is common between person A and person B may not be the same as between person A and person C. [...] The common good has sometimes been seen as a utilitarian ideal, thus representing "the greatest possible good for the greatest possible number of individuals". The "greatest possible number of individuals" would mean all human beings. This definition of the common good presents it as a quality which is convertible, or reducible, to the sum total of all the private interests of the individual members of a society and interchangeable with them.
I might be wrong, but the closest single-word answer for this would be expediency or expedient.
Oxford Dictionaries defines it as:
(of an action) convenient and practical although possibly improper or immoral.
I can think of a common excuse that isn't quite a proverb:
It had to be done
There are also quite a few proverbs that encompass this concept, such as:
You can't make an omelette without breaking eggs.
The end justifies the means.
You have to be cruel to be kind.
Spare the rod and spoil the child.
(As one might expect, there is also at least one proverb that expresses the opposite notion:
He who lives by the sword shall die by the sword. )
But I can't think of a single word that embodies it; I don't think there is one. (Which isn't surprising, because it's a fairly complex idea.)