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Engineering EthicsME 101 – Fall 2008{Modified 10/23/06}

Technology - Defines what we can do.Ethics - Defines what we ought to do.

Politics - Defines what we will do.

What is Morality?

"Engineering ethics is (1) the study of the moral issues and decisions confrontingindividuals and organizations involved in engineering and (2) the study of relatedquestions about moral conduct, character, ideals, and relationships of people andorganizations involved in technological development." M&S, p.4

"To say that an act is right is not to express a mere feeling or bias, but instead toassert that the best moral reasons support doing it." M&S p. 32

What are the Moral Problems which Confront Us?

"... ethical problems arise most often when there are differences of judgment orexpectations as to what constitutes the true state of affairs or a proper course ofaction." M&S, p.7

"... when we speak of moral problems we have in mind situations where whatought to be done is not so straightforward and obvious."

"First, it may be unclear ... which, if any, moral considerations or principles applyto their situation."

"Second, the difficulty might be that two different moral principles, both of whichapply to one's situation, come into conflict or that one principle seems to pointsimultaneously in two different directions." M&S p.25

What is a Moral Theory?

"...there ought either to be some one fundamental principle or law, at the root ofall morality, or if there be several, there should be a determinate order of precedenceamong them; and the ... rule for deciding between the various principles when theyconflict, ought to be self-evident." Mi p.274

What are the Sanctions of Morality?

Feelings of Guilt - consciencePublic Exposure - humiliationPublic (Legal) Punishment

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FOUR BASIC TYPES OF MORAL THEORY:

1.) VIRTUE ETHICSVirtue ethics is the oldest of the moral theories, often "rules" based – sometimes

based upon “Divine Command.”

The emphasis is on becoming a morally good person as opposed to acting in a moralmanner. It is a teleological ethical system from telos (goal or end) considering thebasic question: What does it mean to be a good person?

Three basic concepts are derived from Greek Philosophy:Arête – excellence or virtuePhronesis – practical or moral wisdomEudaimonia – happiness or flourishing.

Virtues are acquired habits that enable us to engage effectively in rational activities."Virtues are desirable ways of relating to other individuals, groups, andorganizations. They have as much to do with motives, attitudes, and emotions, asthey do with right and wrong conduct." M&S, p.40

Moral actions are based on virtue. Wrong actions arise from bad character traits –vices

The rewards of living a virtuous life can vary from eudaimonia – a serene andrespected old age - to entry into heaven or similar metaphysical rewards.

Some Major Proponents of Virtue:Plato – discussed the four cardinal virtues in the Symposium.

Aristotle (384-322 BC) Virtues enable one to have a happy life (an active life based upon reason.) Listed four cardinal virtues: wisdom (prudence), courage (fortitude), temperance,

and justice. "Unity of Virtues" to have one cardinal virtue is to have them all Other authors have expanded the list of cardinal virtues to include: integrity, unity

of character, honesty and self-respect.

St. Thomas Aquinas – Summa Theologiae and Commentary on Nicomachean Ethics

David Hume and the Scottish enlightenment.

PROFESSIONAL VIRTUES:Responsibility is the fundamental professional virtue

some aspects of responsibility include:

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can be counted on to do the right thingconscientiousdiligent in meeting obligationstrustworthyconsiderate of others

There are different viewpoints on what responsibility means. A responsibleperson: has the capacity to make moral judgments. makes a conscientious effort to meet the obligations of one's work. is accountable for actions and their consequences.

Accountability - implies that the action is not completely involuntary

Aristotle defined involuntary as:1.) acts done in ignorance, although ignorance can itself be a moral failing2.) acts performed under compulsion

Responsibility in this sense has two different connotations: Causal and Legal

Self-direction Virtues: self understanding, humility, moral autonomy, courage, self-discipline, perseverance, self respect, integrity, honesty

Public Spirited Virtues: beneficence, generosity, sense of communityTeam Work Virtues: collegiality, cooperation, respect for authority, loyaltyProficiency Virtues: competence, diligence, creativity.

Often , virtue ethics are associated with religious teachings. Divine CommandEthics stipulates that an act is right if commanded by God, and wrong ifforbidden by God.

2.) RIGHTS ETHICS

John Locke (1632-1704)people have "natural" rights - life, liberty, the property generated by one's labor

and the pursuit of happiness.Locke viewed rights as entitlements that prevent other people from meddling in

other's lives - these Liberty, or negative rights, place duties on other people not tointerfere with one's life

our duties to other people arise from our moral need to respect their rights.

A.I. Melden (1910-1991) argued that having moral rights presupposes the capacity toshow concern for others and to be accountable within a moral community.Melden called these Welfare, or positive, rights. These are the rights we each haveto the community benefits needed for living a minimally decent life.

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3.) DUTY ETHICS

" ... there are duties ... which ought to be performed even though doing so maynot always produce the most good." M&S p.33

Immanuel Kant (1724-1804) - Four Types of Duties:Perfect duties to oneself - perfect duties are things that must be donePerfect duties to othersImperfect duties to oneself - imperfect duties are things that should be doneImperfect duties to others

First and foremost, Kant said we have a duty to show respect for people. Peopledeserve this respect because they have inherent worth as human beings who havethe capacity to make moral judgments and to act with good will. This capacitygives them "human dignity."

We must not use people as means to our own ends.

To Kant good will is the only unconditional good.

Duties to ourselves are also fundamental - they engender integrity and self respect.

Duties must be universalizable - they must apply to everyone. They must becategorical imperatives - that is they apply without qualifications or attachedconditions.

Moral imperatives require us to do certain things whether we want to or not. It is ourduty whether it makes us happy or not.

Prima Facie Duties - are duties that have conditions that can lead to exceptions.

John Rawls extended duty ethics on the basis of two imperatives:1.) each person is entitled to the most extensive amount of liberty compatible with an

equal amount for others2.) differences in social power and economic benefits are justified only when they are

likely to benefit everyone, including members of the most disadvantaged groups.

4.) UTILITARIANISM - Utility is the overall balance of good over bad. John StuartMill (1806-1873) was the major proponent of this ethical theory.

"Utilitarianism holds that we ought always to produce the most utility, taking intoequal account everyone affected by our actions." M&S p.33

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"Utility, or the Greatest Happiness Principle, holds that actions are right inproportion as they tend to promote happiness, wrong as they tend to produce thereverse of happiness. By happiness is intended pleasure, and the absence of pain; byunhappiness, pain, and the privation of pleasure. ... pleasure, and freedom from pain,are the only things desirable as ends; and that all desirable things ... are desirableeither for the pleasure inherent in themselves, or as means to the promotion ofpleasure and the prevention of pain." Mi p.278

"The standard of right conduct is maximization of goodness." M&S p.35

"Act-Utilitarianism says we should focus on individual actions, rather thangeneral rules. An act is right if it is likely to produce the most good for the mostpeople involved in the particular situation." M&S p.35

"Rule-Utilitarianism regards moral rules as primary … we ought always to onthose rules that if generally followed would produce the most good for the mostpeople." Rule utilitarianism is designed to close the loopholes which are part of actutilitarianism by discounting the pleasure of an individual when compare to a group.

"Mill believed that happiness is the only intrinsic good .. all other good things areinstrumental goods in that they provide means for happiness." M&S p.35

"One kind of pleasure is preferable to another if the majority of people who haveexperienced both kinds favor it." M&S p.35

HISTORICAL DEVELOPMENT OF ETHICAL THEORY

Plato (429-348 BC)Biography:

Founded the Academy about 389 BC in a sacred grove on the outskirts ofAthens.

The school operated until closed by Justinian in AD 529.Intended to " ... train its pupils to carry out a life of service for their

communities and to investigate questions of science and mathematics." Moral arguments from the dialog "Protagoras" c. 370 BC:

"The kind of instruction ... which you received from your instructors in lettersor music or athletics? Under each of these you were instructed so that youcould acquire not some skill or profession, but the kind of liberaleducation suitable for a free man of independent means." p. 140.

"Even in private life our best and wisest citizens are unable to pass on thisexcellence to others." {the wise man cannot lead others to virtue} ... helets them roam free, like sacred flocks, in the hope that they will somehowstumble upon this excellence of their own accord." p. 148.

REFERENCES:

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Mike W. Martin and Roland Schinzinger, Ethics in Engineering, Second Edition, McGraw-Hill, 1989. {M&S}

Alan Ryan, Editor, John Stuart Mill and Jeremy Bentham - Utilitarianism and OtherEssays, Penguin Classics, 1987.

J.S. Mill, "Utilitarianism" (1861), pp. 272-338. {Mi}George C. Kerner, Three Philosophical Moralists: Mill, Kant, and Sartre - An

Introduction to Ethics, Oxford University Press, 1990.Erich Segal, Editor, The Dialogues of Plato, Bantam Books, 1986"Protagoras", pp.137-191 {Pl}

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ETHICAL ASPECTS OF ENGINEERING PRACTICE

The Engineer's Responsibilities to the PublicPublic Safety and Welfare and Volunteerism

- Public Safety is the paramount responsibility of the engineer.- The "Public" can be subdivided into four groups, each of which can lay claim toa different level of responsibility from the practicing engineer:

Expert - an expert consumer should thoroughly understand the use andpotential for misuse of the engineered system. By virtue of this expertknowledge the expert consumer is completely responsible for their use ofthe artifact. The designer has the responsibility of developing the "best"solution to the consumer's specific problem, but does not share the user'sresponsibility on how the system is actually used.

As an example, consider the race car driver who purchase's brakecomponents for his/her automobile. The producer's sole responsibility is toinsure that these components have been manufactured to the publishedspecifications.

Active Consumer - the active consumer has the knowledge required tooperate and maintain the device. The active consumer assumes some ofthe responsibility by making sure the device is operated in a safe manner,but the designer must insure that the device is intrinsically safe if operatedproperly, and properly maintained. An airline pilot is an example of anactive consumer.

Passive Consumer - such as an airliner passenger, assumes no responsibilityfor the operation of a system. The designer must offer the passiveconsumer protection from the consequences of a system failure -consistent with the economic interests of the consumer.

Innocent Bystanders - must not be harmed by the failure of an engineeringsystem under any circumstances. They have not assumed any of theresponsibility for the operation of that system.

Expert Information on Public IssuesWhistleblowing

The Engineer's Responsibilities to the ClientDisclosure of Design ErrorsConfidentialityAdherence to CodeMonitoring of Sub-Contractors

The Engineer's Responsibilities to the ProfessionPro bono Recruiting/Service to Public Institutions.

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Participation in Professional Societies

Conflict of Interest - Occurs whenever an engineer is in a position to make a decisionthat can result in his/her personal gain.Disclosure of Potential Conflict of InterestContingency PaymentsCompetition with Former EmployersRelated Private Consultation After Public Employment

Fair Trade PracticesIntellectual Property RightsCriticism of Competitors CompetenceInflated Claims in AdvertisingShared CreditMaintaining Professional Standards

Letters of RecommendationSigning off on Drawings

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DESIGN FOR SAFETY AND RELIABILITY

"Accidents don't just happen, ... they are permitted to happen by foolswho take no thought of misadventure!" William Nelson Cromwell

Things fail! Engineers are expected to predict these potential failures and controlthem in their designs. Great engineers of the past have often reported that they have lostsleep worrying about the design problems they were working on, and anticipating thekinds of problems that might be encountered far into the future.

"A safe structure will be one whose weakest link is never overloaded by the greatestforce to which the structure is subjected." Petroski p. 41.

"all successful design is the proper and complete anticipation of what can go wrong."Petroski, p. 6

" all error is human error, because it is people who have to decide what to do; it ispeople who have to decide how it should be done; and it is people who have to do it."Blockley 1980.

A disaster takes place when a seriously disruptive event (an emergency) coincideswith a state of insufficient preparation.

Safety - a thing is safe if the risks, if they are fully known, are judged to be acceptable inlight of well established principles and values. In this sense, safety is a subjectiveconcept since the "values" used to assess it vary from person to person.

Risk (I) - the potential that something unwanted and harmful may occur.

Risk (II) - The product of the probability of an event occurring multiplied by theconsequences if that event occurs.

An engineering system (structure, machine, network or process) will either fail to fulfillits function or it will succeed!

While there are many modes of failure, and many mechanisms for triggering thesemodes, we can measure the performance of a system over a period of time and define anumerical “Probability of Failure.” This is usually shown as a function of time:

PF(t) = probability that a system will fail before a specified time = number of failures upto time t divided by the number of systems that were put into service at time zero.

Usually the probability of failure is specified by a statement defining the relativeoccurence such as “one in a hundred,” which is numerically equivalent to 1/100 or 0.01

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Failure and success are mutually exclusive. If something doesn’t fail it survives. Theprobability of a system surviving, up to time t, is called the Reliability of the system andis denoted by the symbol R(t).

The probability of failure and the reliability are related by the equation:

PF(t) + R(t) = 1

So, the reliability of a system that must not fail more than 1 in a 100 times up to time t is:

R(t) = 1 – 0.01 = 0.99

This inter-relationship is summarized in the following table:

Occurrence Probability of Failure Reliability1 in 10 0.1 0.91 in 100 0.01 0.99

1 in 1000 0.001 0.9991 in 10,000 0.0001 0.9999

1 in 100,000 0.00001 0.999991 in 1,000,000 0.000001 0.9999991 in 10,000,000 0.0000001 0.9999999

Another measure of Reliability that is often used is the Mean Time Between Failures(MTBF). The MTBF is defined as the time it takes for the reliability to fall to 0.632 (1/e.)The reliability can then be expressed by the relationship:

€

R(t) = e−

tMTBF

which is useful in computations. Many consumer products, light bulbs for example,actually show the MTBF on their packaging as a marketing ploy.

The Reliability of Engineering Systems:

Series Systems: A mechanical system is defined as a “series” system if the failure of anyone part in the “reliability chain” causes the failure of the entire system. See the exampleon the next page.

The reliability of a series system is the product of the reliabilities of all of the elements inthe chain:

€

Rsys(t) = Ri( t)i=1

N

∏ = R1× R2 × ...× RN

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Note that the over-all reliability of a series system is lower than the lowest reliability ofany of the components it is made up of!

Parallel Systems: A mechanical system is organized in “reliability parallel” if all theelements in the system must fail before the system itself fails. In this kind of system thereare other “paths” that will support the system’s operations should one fail. For example,all commercial jet aircraft are designed with multiple engines. In general, a jet cancontinue to fly and land as long as any one engine is working.

For a parallel system the probability of failure for the overall system is the product of theprobabilities of failure of all of the individual elements:

€

PFsys = PFi =1− Rsys = (1− Ri)i=1

N

∏i=1

N

∏

or,

€

Rsys =1− (1− R1) × (1− R2) × ...× (1− RN )

Theoretically, the reliability of a parallel system is always greater than the reliability ofthe best element in the system. Parallel elements are also called Redundant elements.

EXAMPLE: An Automobile Ignition Distributor:

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R = 0.9995

R = 0.99

R = 0.99

} R = 0.999, combined

R = 0.9999

The working parts of an automobile ignition system’s distributor cap are shown above.This system has many ways of failing. The connection to the coil can loosen or corrode,the breaker points can be fouled by electrical arcing, and can be shorted by humidity ifthe distributor cap cracks. The adjusting screw can loosen up and foul up the ignitiontiming. The cam and cam follower are continuously subject to wear. Not shown in thisfigure is a spring that keeps the face of the follower in contact with the cam. Finally thecapacitor is subject to electrical and environmental damage.Approximate reliabilities for 5000 hours of operation are shown in the table. Since theignition system will fail if any of these elements fail the system is in series. Thereliability of the entire distributor can be estimated as:

Rsys = (0.9995)(0.99)(0.99)(0.999)(0.9999) = 0.978

or, 22 units per thousand will fail before 5000 hours of operation. If we wanted toimprove the design we can see that the weak links are the breaker points and adjustmentscrew.

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EXAMPLE: A Modern Wire Rope Elevator

The passenger car (5) of the elevator shownat the left is suspended by three cables. Ifany one of these cables is capable ofsupporting the entire load then the systemis organized in reliability “Parallel” or, twoof the cables are said to be redundant.

Assume that the cable has been designed sothat the reliability, under full load, for10,000 hours of operation, is 0.999. Themanufacturer warrants that a single cablehas a 1 in 1000 chance of failing over thedesign life. What is the reliability of thetotal elevator system?

1 – Rsys = (1 – R cable)3

Rsys = 1 – (1 – 0.999)3 = 0.999999999

Or, there is a one in a billion chance theentire elevator system will fail, droppingthe passenger car, in 10,000 hours!

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There are, of course, more complicated ways of arranging mechanical elements. Oneother that is mentioned here for the sake of completeness is the “k of m” system. Thistype of system will continue to operate as long as “k of the original m” parallel elementscontinue to operate. The equation for calculating the reliability of a system like this is:

€

Rsys =m!

(m − j)!( j)!j= k

m

∑ R jj (1− R j )

(m− j )

The Management of Risk

It is an inescapable fact of life that engineers cannot design a system that will not fail!

“The only ship that will not sink is one that sits on solid ground, butthat is not what ships are for!”

The engineer’s task is to keep the risk of each possible failure at an acceptable level.

As described earlier the risk can be defined as:

Risk = (Probability of Failure) x (Consequences of Failure)

The consequences of failure may be described in terms of lost time, lost dollars, or, inextreme cases, lost lives. To compare alternatives it is necessary to express risk in thesame “units.”

Note there are two ways to control the value of risk inherent in a design. The engineercan either:

Control the probability of failure, the goal of “Fail Safe Design”or,

Control the consequences of failure resulting in a “Safe Fail Design.”

In Fail Safe Design the maximum probability of failure (or, alternatively, thereliability) for the design is specified at the outset of the project. The organization of thesystem and the selection of the individual elements are then manipulated to match thesystem goal.

The PF for a Series system can only be controlled by using components,manufacturing and quality control techniques of such high quality that their individualreliabilities are much higher than the target reliability of the entire system. If parts thatare that good exist then they are going to be frightfully expensive!

FACTORS THAT MAKE A HIGH QUALITY COMPONENT:- Good, high quality materials- Good manufacturing techniques- Good quality control procedures

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- Careful handling and shipping- Carefully monitored use- Frequent maintenance

EXAMPLE: The space shuttle is protected by 30,000 thermal ablation tiles. 2000 of thesetiles protect vital areas. If the loss of any one of these tiles could jeopardize the shuttle’ssafety what must the individual reliability of these critical tiles be if the over-allprobability of failure the shuttle is to remain below 1 in a 100 missions?

0.99 = R2000

R = 0.999995

Or only five tiles in a million could be permitted to fail during testing!