Deontology: Definition, Theory, Ethics & Examples

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  • 0:00 Understanding Ethics
  • 1:12 Kant's Deontology Defined
  • 2:35 Deontology vs. Utilitarianism
  • 5:30 Kath's Categorical Imperative
  • 8:19 Lesson Summary
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Lesson Transcript
Instructor: Jennifer Keefe

Jennifer Keefe has taught college-level Humanities and has a Master's in Liberal Studies.

The question of doing what is right or what is wrong took on a new meaning in the 18th century. In this lesson, learn about a branch of ethics called deontology. Then, take a short quiz to test your knowledge.

Understanding Ethics

You think you know the difference between right and wrong, don't you? Where the idea of right and wrong comes from is a question that stems from a branch of philosophy known as ethics. Ethics can be really hard to define, since what you think is right, or ethical, might be very different from what your friends or family members think.

However, ethics is loosely defined as established standards of right and wrong that spell out what people should and should not do in a society, the rights they have, and what benefits they should gain from being a member of society. These are the standards we establish that keep us from hurting others because, in our beliefs, hurting others is wrong. From an individual standpoint, ethics could be defined as our own established standards of right and wrong.

The problem is, everyone's ideas about what is ethical are different. Plus, there are situations where something we know is wrong, like shooting someone, suddenly becomes right to an individual, like choosing to shoot an intruder who breaks into your home and threatens your family.

Kant's Deontology Defined

In the 18th century, the Age of Enlightenment was in full swing. People were beginning to rely on the principles of natural law, which states that there is a right and a wrong and that we must use reason, or our personal sense of logic, to figure out the difference. During this time, a German philosopher named Immanuel Kant developed a branch of ethics that was solely based upon one's sense of duty to act in the way we see as right. Kant's deontology is guided by an individual's own personal sense of morality, or what is right and what is wrong to us. Kant was a scientist and scholar whose books included works about science, morality, and history.

Kant's deontology, sometimes called deontological ethics, starts by acknowledging that actions and their outcomes are independent things. Basically, there are things you have to do, even though you know they are wrong, such as shooting that intruder to protect your family. According to deontology, you need to focus on the act, such as protecting your family, and not the likely death it will mean for the intruder. Kant wrote several books about the topic, including The Groundwork of the Metaphysics of Morals in 1785, Critique of Practical Reason in 1788, and Metaphysics of Morals in 1797.

Deontology vs. Utilitarianism

Deontology is sometimes best understood when you try to compare it to another social theory. Are you familiar with utilitarianism? Utilitarianism is a branch of consequentialism. Utilitarianism is the idea that the action that is the most moral (or seems the most right) is the one that creates the most good for all parties involved. The idea isn't fully spelled out until the 19th century. Social theorists John Stuart Mill and Jeremy Bentham, both British and classical utilitarians, identify the idea of good with pleasure and believe that people should attempt to achieve the most good for everyone. In utilitarianism, everyone's happiness counts the same.

So, you should consider the rights and needs of that intruder before you shoot him, according to Bentham and Mill (and maybe tie him up and call the cops, or shoot him in a non-fatal location). On the other hand, deontology considers what benefits you and the people you care about, not necessarily what is good for society or anyone else. Kant tells you to shoot the intruder with the intent to kill, even though it is morally wrong, because it is your duty to protect your family.

To compare the two philosophies, we can say that utilitarianism says that any act that achieves happiness through consideration of all sides should be considered good (not killing the man in your living room, but also making sure your family is safe). While deontology states that some actions are still morally wrong even if the outcome is good, but you should do them anyway because of your sense of duty to others (kill the man in your living room because it is your duty to protect your family and not your problem what happens to him). In deontology, actions and outcomes are measured separately, which is not the case in utilitarianism. Deontology states that an act that is not good morally can lead to something good, such as shooting the intruder (killing is wrong) to protect your family (protecting them is right).

According to Kant, morality is affected by rational thought moreso than by emotion. Human nature (which might tell you to protect your family) has nothing to do with morality (which tells you killing is wrong) because human beings are rational enough to make case-by-case decisions. Remember, this is the era of the Enlightenment, also known as the Age of Reason, where thinkers of the time were moving away from the societal confines and morality-based teachings of the Catholic Church toward thinking and acting for themselves. Ideas of the time included studies of the role of the citizens in government and society, advances in science, and the development of an overall belief in man's self-reliance, as opposed to reliance on God. In our example, that means protecting your family is the rational thing to do—even if it is not the morally best thing to do.

Kath's Categorical Imperative

In 1785, Kant published The Groundwork of the Metaphysics of Morals, a book in which he defined the idea of the categorical imperative. The categorical imperative is a major aspect of deontology and is a way of setting man apart from, and putting him above, other species because of his ability to think and act rationally. The laws of the categorical imperative are universal rules to live by, according to Kant, setting the tone for how we act and how we treat one another.

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