Descriptions of Ethical Theories and Principles

Created by Catherine Rainbow for Biology 372 at Davidson College

Ethical theories and principles are the foundations of ethical analysis because they are the viewpoints from which guidance can be obtained along the pathway to a decision. Each theory emphasizes different points such as predicting the outcome and following one's duties to others in order to reach an ethically correct decision. However, in order for an ethical theory to be useful, the theory must be directed towards a common set of goals. Ethical principles are the common goals that each theory tries to achieve in order to be successful. These goals include beneficence, least harm, respect for autonomy and justice (1,2,3,4).

Ethical Principles


The principle of beneficence guides the ethical theory to do what is good. This priority to "do good" makes an ethical perspective and possible solution to an ethical dilemma acceptable. This principle is also related to the principle of utility, which states that we should attempt generate the largest ratio of good over evil possible in the world (2). This principle stipulates that ethical theories should strive to achieve the greatest amount of good because people benefit from the most good. This principle is mainly associated with the utilitarian ethical theory found in the following section of this paper. An example of "doing good" is found in the practice of medicine in which the health of an individual is bettered by treatment from a physician (1,2).

Least Harm

This is similar to beneficence, but deals with situations in which neither choice is beneficial. In this case, a person should choose to do the least harm possible and to do harm to the fewest people. For instance, in the Hippocratic oath, a physician is first charged with the responsibility to "do no harm" to the patient since the physician's primary duty is to provide helpful treatment to the patient rather than to inflict more suffering upon the patient (3,4).

One could also reasonably argue that people have a greater responsibility to "do no harm" than to take steps to benefit others. For example, a person has a larger responsibility to simply walk past a person rather than to punch a person as they walk past with no justified reason (3,4).

Respect for Autonomy

This principle states that an ethical theory should allow people to reign over themselves and to be able to make decisions that apply to their lives. This means that people should have control over their lives as much as possible because they are the only people who completely understand their chosen type of lifestyle. Each man deserves respect because only he has had those exact life experiences and understands his emotions, motivations and body in such an intimate manner. In essence, this ethical principle is an extension of the ethical principle of beneficence because a person who is independent usually prefers to have control over his life experiences in order to obtain the lifestyle that he enjoys (1,4).

There are, however, two ways of looking at the respect for autonomy. In the paternalistic viewpoint, an authority prioritizes a dependent person's best interests over the dependent person's wishes (1). For example, a patient with terminal cancer may prefer to live the rest of her life without the medication that makes her constantly ill. The physician, on the other hand, may convince the patient and her family members to make the patient continue taking her medication because the medication will prolong her life. In this situation, the physician uses his or her authority to manipulate the patient to choose the treatment that will benefit him or her best medically. As noted in this example, one drawback of this principle is that the paternalistic figure may not have the same ideals as the dependent person and will deny the patient's autonomy and ability to choose her treatment. This, in turn, leads to a decreased amount of beneficence.

A second way in which to view the respect for autonomy is the libertarian view. This standpoint prioritizes the patient's wishes over their best interests. This means that the patient has control over her life and should be content with her quality of life because she has chosen the path of life with the greatest amount of personal beneficence. Although this viewpoint is more mindful of the patient's desires, it does not prevent the patient from making decisions that may be more harmful than beneficial (1).


The justice ethical principle states that ethical theories should prescribe actions that are fair to those involved. This means that ethical decisions should be consistent with the ethical theory unless extenuating circumstances that can be justified exist in the case. This also means that cases with extenuating circumstances must contain a significant and vital difference from similar cases that justify the inconsistent decision. An ethical decision that contains justice within it has a consistent logical basis that supports the decision (1,3,4). For example a policeman is allowed to speed on the highway if he must arrive at the scene of a crime as quickly as possible in order to prevent a person from getting hurt. Although the policeman would normally have to obey the speed limit, he is allowed to speed in this unique situation because it is a justified under the extenuating circumstances.

Ethical Theories

Ethical theories are based on the previously explained ethical principles. They each emphasize different aspects of an ethical dilemma and lead to the most ethically correct resolution according to the guidelines within the ethical theory itself. People usually base their individual choice of ethical theory upon their life experiences (1,2).


The deontological theory states that people should adhere to their obligations and duties when analyzing an ethical dilemma. This means that a person will follow his or her obligations to another individual or society because upholding one's duty is what is considered ethically correct (1,2). For instance, a deontologist will always keep his promises to a friend and will follow the law. A person who follows this theory will produce very consistent decisions since they will be based on the individual's set duties.

Deontology provides a basis for special duties and obligations to specific people, such as those within one's family. For example, an older brother may have an obligation to protect his little sister when they cross a busy road together. This theory also praises those deontologists who exceed their duties and obligations, which is called "supererogation" (1). For example, if a person hijacked a train full of students and stated that one person would have to die in order for the rest to live, the person who volunteers to die is exceeding his or her duty to the other students and performs an act of supererogation.

Although deontology contains many positive attributes, it also contains its fair number of flaws. One weakness of this theory is that there is no rationale or logical basis for deciding an individual's duties. For instance, businessman may decide that it is his duty to always be on time to meetings. Although this appears to be a noble duty we do not know why the person chose to make this his duty. Perhaps the reason that he has to be at the meeting on time is that he always has to sit in the same chair. A similar scenario unearths two other faults of deontology including the fact that sometimes a person's duties conflict, and that deontology is not concerned with the welfare of others. For instance, if the deontologist who must be on time to meetings is running late, how is he supposed to drive? Is the deontologist supposed to speed, breaking his duty to society to uphold the law, or is the deontologist supposed to arrive at his meeting late, breaking his duty to be on time? This scenario of conflicting obligations does not lead us to a clear ethically correct resolution nor does it protect the welfare of others from the deontologist's decision. Since deontology is not based on the context of each situation, it does not provide any guidance when one enters a complex situation in which there are conflicting obligations (1,2).


The utilitarian ethical theory is founded on the ability to predict the consequences of an action. To a utilitarian, the choice that yields the greatest benefit to the most people is the choice that is ethically correct. One benefit of this ethical theory is that the utilitarian can compare similar predicted solutions and use a point system to determine which choice is more beneficial for more people. This point system provides a logical and rationale argument for each decision and allows a person to use it on a case-by-case context (1,2).

There are two types of utilitarianism, act utilitarianism and rule utilitarianism. Act utilitarianism adheres exactly to the definition of utilitarianism as described in the above section. In act utilitarianism, a person performs the acts that benefit the most people, regardless of personal feelings or the societal constraints such as laws. Rule utilitarianism, however, takes into account the law and is concerned with fairness. A rule utilitarian seeks to benefit the most people but through the fairest and most just means available. Therefore, added benefits of rule utilitarianism are that it values justice and includes beneficence at the same time (1,2).

As with all ethical theories, however, both act and rule utilitarianism contain numerous flaws. Inherent in both are the flaws associated with predicting the future. Although people can use their life experiences to attempt to predict outcomes, no human being can be certain that his predictions will be true. This uncertainty can lead to unexpected results making the utilitarian look unethical as time passes because his choice did not benefit the most people as he predicted (1,2). For example, if a person lights a fire in a fireplace in order to warm his friends, and then the fire burns down the house because the soot in the chimney caught on fire, then the utilitarian now seems to have chosen an unethical decision. The unexpected house fire is judged as unethical because it did not benefit his friends.

Another assumption that a utilitarian must make is that he has the ability to compare the various types of consequences against each other on a similar scale. However, comparing material gains such as money against intangible gains such as happiness is impossible since their qualities differ to such a large extent (1).

A third failing found in utilitarianism is that it does not allow for the existence of supererogation or heroes. In other words, people are obligated to constantly behave so that the most people benefit regardless of the danger associated with an act (1). For instance, a utilitarian who sacrifices her life to save a train full of people is actually fulfilling an obligation to society rather than performing a selfless and laudable act.

As explained above, act utilitarianism is solely concerned with achieving the maximum good. According to this theory an individual's rights may be infringed upon in order to benefit a greater population. In other words, act utilitarianism is not always concerned with justice, beneficence or autonomy for an individual if oppressing the individual leads to the solution that benefits a majority of people. Another source of instability within act utilitarianism is apparent when a utilitarian faces one set of variable conditions and then suddenly experiences a change in those variables that causes her to change her original decision. This means that an act utilitarian could be nice to you one moment and then dislike you the next moment because the variables have changed, and you are no longer beneficial to the most people (1).

Rule utilitarianism also contains a source of instability that inhibits its usefulness. In rule utilitarianism, there is the possibility of conflicting rules (1). Let us revisit the example of a person running late for his meeting. While a rule utilitarian who just happens to be a state governor may believe that it is ethically correct to arrive at important meetings on time because the members of the state government will benefit from this decision, he may encounter conflicting ideas about what is ethically correct if he is running late. As a rule utilitarian, he believes that he should follow the law because this benefits an entire society, but at the same time, he believes that it is ethically correct to be on time for his meeting because it is a state government meeting that also benefits the society. There appears to be no ethically correct answer for this scenario (1).


In the rights ethical theory the rights set forth by a society are protected and given the highest priority. Rights are considered to be ethically correct and valid since a large or ruling population endorses them. Individuals may also bestow rights upon others if they have the ability and resources to do so (1). For example, a person may say that her friend may borrow the car for the afternoon. The friend who was given the ability to borrow the car now has a right to the car in the afternoon.

A major complication of this theory on a larger scale, however, is that one must decipher what the characteristics of a right are in a society. The society has to determine what rights it wants to uphold and give to its citizens. In order for a society to determine what rights it wants to enact, it must decide what the society's goals and ethical priorities are. Therefore, in order for the rights theory to be useful, it must be used in conjunction with another ethical theory that will consistently explain the goals of the society (1). For example in America people have the right to choose their religion because this right is upheld in the Constitution. One of the goals of the founding fathers' of America was to uphold this right to freedom of religion. However, under Hitler's reign in Germany, the Jews were persecuted for their religion because Hitler decided that Jews were detrimental to Germany's future success. The American government upholds freedom of religion while the Nazi government did not uphold it and, instead, chose to eradicate the Jewish religion and those who practiced it.


The casuist ethical theory is one that compares a current ethical dilemma with examples of similar ethical dilemmas and their outcomes. This allows one to determine the severity of the situation and to create the best possible solution according to others' experiences. Usually one will find paradigms that represent the extremes of the situation so that a compromise can be reached that will hopefully include the wisdom gained from the previous examples (2).

One drawback to this ethical theory is that there may not be a set of similar examples for a given ethical dilemma. Perhaps that which is controversial and ethically questionable is new and unexpected. Along the same line of thinking, a casuistical theory also assumes that the results of the current ethical dilemma will be similar to results in the examples. This may not be necessarily true and would greatly hinder the effectiveness of applying this ethical theory (2).


The virtue ethical theory judges a person by his character rather than by an action that may deviate from his normal behavior. It takes the person's morals, reputation and motivation into account when rating an unusual and irregular behavior that is considered unethical. For instance, if a person plagiarized a passage that was later detected by a peer, the peer who knows the person well will understand the person's character and will be able to judge the friend. If the plagiarizer normally follows the rules and has good standing amongst his colleagues, the peer who encounters the plagiarized passage may be able to judge his friend more leniently. Perhaps the researcher had a late night and simply forgot to credit his or her source appropriately. Conversely, a person who has a reputation for scientific misconduct is more likely to be judged harshly for plagiarizing because of his consistent past of unethical behavior (2).

One weakness of this ethical theory is that it does not take into consideration a person's change in moral character. For example, a scientist who may have made mistakes in the past may honestly have the same late night story as the scientist in good standing. Neither of these scientists intentionally plagiarized, but the act was still committed. On the other hand, a researcher may have a sudden change from moral to immoral character may go unnoticed until a significant amount of evidence mounts up against him or her (2).

Ethical theories and principles bring significant characteristics to the decision-making process. Although all of the ethical theories attempt to follow the ethical principles in order to be applicable and valid by themselves, each theory falls short with complex flaws and failings. However, these ethical theories can be used in combination in order to obtain the most ethically correct answer possible for each scenario. For example, a utilitarian may use the casuistic theory and compare similar situations to his real life situation in order to determine the choice that will benefit the most people. The deontologist and the rule utilitarian governor who are running late for their meeting may use the rights ethical theory when deciding whether or not to speed to make it to the meeting on time. Instead of speeding, they would slow down because the law in the rights theory is given the highest priority, even if it means that the most people may not benefit from the decision to drive the speed limit. By using ethical theories in combination, one is able to use a variety of ways to analyze a situation in order to reach the most ethically correct decision possible (1).

We are fortunate to have a variety of ethical theories that provide a substantial framework when trying to make ethically correct answers. Each ethical theory attempts to adhere to the ethical principles that lead to success when trying to reach the best decision. When one understands each individual theory, including its strengths and weaknesses, one can make the most informed decision when trying to achieve an ethically correct answer to a dilemma.

References Cited

1. Ridley, Aaron. 1998. Beginning Bioethics. New York: St. Martin's Press.

2. Penslar, Robin L,. 1995. Research Ethics: Cases and Materials. Bloomington: Indiana University Press.

3. "General Ethical Foundation." Online. Accessed February 17, 2002.

4. "Ethical Principles." Online. Accessed February 17, 2002.,%20Ethical%20Principles.htm

© Copyright 2002 Department of Biology, Davidson College, Davidson, NC 28035
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