methods & tools of analysis csci102 - systems itcs905 - systems mcs9102 - systems

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Methods & Tools of Analysis CSCI102 - Systems ITCS905 - Systems MCS9102 - Systems

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Methods & Tools of Analysis

CSCI102 - Systems

ITCS905 - Systems

MCS9102 - Systems

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Ethics & Morality

• Ethics

– From the Greek ethos

• Morality

– From the Latin mores

• Both refer to character, habit and behaviour

• Ethics is the Study of Morality

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What is Morality?

• There is no agreed definition• Rules of human conduct

• Two kinds of rules of conduct

1. Directives to guide individuals (microlevel)

• Eg: do not steal, do not kill

2. Social Policies (macrolevel)

• Eg: software should be protected, respect privacy

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Moral Systems

• A system whose purpose is to prevent harm and evil

– Bernard Gert (1998)

• … and should promote human flourishing

– Louis Pojman (2001)

• Are Public & Informal, Rational & Impartial (Gert)

– PUBLIC:everyone must know the rules

– INFORMAL:there is no authority enforcing it

– RATIONAL:based on the principles of logic

– IMPARTIAL:apply equally to all

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Deriving & Justifying a Moral System• Grounds for justifying a moral system

– Religion

• Obedience to divine authority

• Difficult in a pluralistic heterogeneous society

– Legal

• Obedience to a legal system

• Laws not uniform across national boundaries

– Philosophy

• Ethical theory

• Appeal to logical arguments to justify claims and positions

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Cultural & Moral Relativism

• Cultural relativity:

– Different cultures may have different concepts of right & wrong

– Can right and wrong in a society only be determined by members of that society?

• Moral relativity:

– Says, no universal standard of morality is possible because different people have different beliefs about what is right & wrong

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Why do we need Ethical Theories?

• Why not just use the so-called ‘Golden Rule’ or simply ‘follow your conscience’?

• Golden Rule: do unto others as you would have them do unto you

– Assumes what you’d accept or desire is what others would accept or desire!

• Follow your conscience

– Conscience is subjective, and is therefore neither rational or impartial

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Structure of Ethical Theories

• Must be coherent and comprehensive• Cannot contain ad hoc, patchwork components

– The “Bork Bill”

• Judge Robert Bork was nominated for the Supreme Court.

• Reporters went to a video store to find out what kinds of movies Bork rented.

• The US Congress was incensed and passed the Video Protection Act

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Consequence-Based Ethical Theories• Some argue the ends are the best test,

as ethical systems are designed to produce desirable outcomes

• Utilitarianism: act for the greater good

– People desire happiness, happiness is therefore good

– If one action makes more people happy than another, it must be better than the other

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Consequence-Based Ethical Theories• Act utilitarianism

– ‘greatest good’ results for the majority may require very bad results for a minority

• Rule utilitarianism

– Establish ‘good rules’ to benefit society, and actions that lie within that rule are acceptable

• Critics dismiss utilitarianism because it is grounded in consequences and happiness … “I wont help you with your problem because it wont make me happy”

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Duty-Based Ethical Theories

• Duty and obligation (Immanuel Kant 1724-1804)

• It is right that we must do our duty, even it it makes us unhappy

– Humans are essentially rational in nature and can recognize obligations to each other

– Humans are an “end” in themselves – ie: no human may be a “means to an end”

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Contract-Based Ethical Theories• Contractual agreements between individuals

– Rational beings see the advantage of co-operation to gain a better life (Thomas Hobbes 1588-1679)

• Social-contract theory criticized as minimalist – ie: only applies where rules and formal contracts exist

– Leads legalistic behaviour, remember Telstra and the teletypewriter?

– No requirement to do good, merely a rule to do no harm

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Contract-Based Ethical Theories• Rights based contract theories

– Negative rights:right not to be interfered with, eg: right to own a computer ~ no one is obliged to provide one, but no-one may prevent you from having one

– Positive rights:very rare! And controversial … eg: US right to receive an education … so does that mean they must receive the tools and equipment etc? ‘net access?

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Character-Based Ethical Theories

• Virtue ethics.

– Focus on character development and acquiring good traits from their habits (Plato, Aristotle c.400BC, Alasdair MacIntyre 1981)

• Being a moral person

– Requires the right training to acquire the right qualities

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Character-Based Ethical Theories

• Acquiring correct habits

– When ‘good behaviour’ becomes habit, it no longer requires a conscious decision

– Difficult to put in place in a large heterogeneous society

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A Comprehensive Theory?

• James Moor’s just-consequentialist theory (1999)

– What kind of conduct do we want ethics to regulate?

• ID a set of ‘core values’ common to all cultures

• A desirable objective of ethics is to support justice, rights and duties

– IF all we had to do was ‘do no harm’ and perform our duties, ethics would be easy to understand … BUT … we have to be able to decide between conflicting options

– Decision process has two steps:

• Deliberation

– Use an impartial standpoint

• Selection

– Weigh the good and bad consequences of the choices

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Tools for Evaluating Cyberethical Issues

• As we have seen, logic forms a basis for rational and impartial theorising about ethics

• We can begin to evaluate ethical issues by testing the logical validity of claims and statements

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Logical Arguments

• Structure of a logical argument:

– PREMISE 1

– PREMISE 2 (optional)

– PREMISE 3 (optional)

– …

– PREMISE n (optional)_________________

– CONCLUSION

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Identifying Logical Fallacies

• Fallacy refers to “faulty reasoning”, not “being wrong” … as a fallacious argument can be constructed out of all true statements!

• Next we see ten ‘informal logical fallacies’ to assist you to identify fallacious arguments

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Identifying Logical Fallacies

• Ad hominem argument

– Attack directed to the person rather than to the substance of the person’s argument

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Identifying Logical Fallacies

• Slippery Slope argument- “edge of the wedge”

– “X could possibly be abused, so we should not allow X”

– “swords can kill, so lets remove them all from society before we all get killed”

– Fallacy in assuming that the worst consequence will inevitably follow … the argument itself contains no evidence to that effect

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Identifying Logical Fallacies

• Fallacy of Appeal to Authority

– PREMISE 1: X is an authority in Y

– PREMISE 2: X said Z______________________

– CONCLUSION: Z

– An expert chef may have an opinion regarding a brand of oven, but are they necessarily an expert in electrical design etc?

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Identifying Logical Fallacies

• False cause fallacy (post hoc ergo prompter hoc – after this, therefore because of this)

– Just because X preceded Y, does not mean that X caused Y

– Circular logic:the truth of the premise presupposes the truth of the conclusion, rather than supplying the evidence for the conclusion

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Identifying Logical Fallacies

• Begging the question

– The premise presupposes the truth of the conclusion it is trying to establish (circular logic again)

– Eg: “OO programming languages are superior to non structured programming languages because OO languages are structured”

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Identifying Logical Fallacies

• Fallacy of Composition

– Confuses the characteristics that apply to the parts of a whole, with the characteristics of the whole itself

• Eg: “Brand X PC is the best because it has the fastest processor and twice the RAM and comes with a better suite of software than any other”

• Eg: “this film has academy award winning stars in it – so it must be an academy award winning film”

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Identifying Logical Fallacies

• Fallacy of Division

– Infers attributes that apply to the whole must apply to the parts

• Eg: “This was voted the best computer in 2002, so it must have had the most advanced graphics card”

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Identifying Logical Fallacies

• Fallacy of Ambiguity

– One or more terms used ambiguously

• Eg: “humans think and computers think, so computers are human”

• Eg: ‘Computers have memory. Memory allows us to remember our childhood. So, Computers can recall their childhood”

• NO – because the terms “think” & “memory” are ambiguous, the ‘thinking’ each of these entities does is not the same thing, and the ‘memory’ is not of the same kind

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Identifying Logical Fallacies

• Appeal to the People (Argumentum ad Populum)

– Assumption that there is strength in numbers

– “greatest album ever! 50 million Elvis fans cant be wrong!”

– “slavery is cool, 100 million slave owners cant be wrong!”

– “its OK to pirate music, everyone does it!”

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Identifying Logical Fallacies

• The Many / Any Fallacy

– PREMISE 1: many items of kind A have feature B_______________________________________

– CONCLUSION: any item of kind A has feature B

– “There are many acceptable ways to travel from Sydney to Hong Kong, therefore it is acceptable to travel from Sydney to Hong Kong by bicycle”

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Identifying Logical Fallacies

• The Virtuality Fallacy

– PREMISE 1: X exists in cyberspace

– PREMISE 2: cyberspace is virtual____________________________

– CONCLUSION: X (or effect of X) is not real

– Virus attacks?

– Pornography?

– Paedophilia?

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Constructing an Argument

• Arguments are used to justify things, to convince people of things etc.

• Generally arguments will succeed or not depending on how well constructed they are, and on their “argument strength”

• How do we determine argument strength?

– Need to understand difference between valid & invalid arguments

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Valid & Invalid Arguments

• We can use an informal system developed by John Nolte (1984).

– Don’t need to know anything about the truth of the claims in the argument, we determine if the arguments conclusions would necessarily follow from its premises (when they are all assumed to be true)

– To demonstrate an argument is INVALID, we need only find one counterexample

• This isn’t enough though: for “sound” argument,we need to test IF the premises are true in the real world …

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Sound Arguments

• Soundness is a test of the truth in the real world of the premises in an argument.

• A valid argument can be sound or unsound.

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Invalid Arguments

• Has at least one counterexample, even if the premises and conclusion are true in the real world.

• PREMISE 1: all CEO’s of major US software corp’s have been US citizens

• PREMISE 2: Bill Gates is a US citizen______________________________________

• CONCLUSION: Bill Gates is CEO of a major US software corp.

• Try substituting “Julia Roberts” or “George Bush” ?This is invalid because there are counter examples

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Inductive Arguments

• Not all invalid arguments are weak however• Some are inductive

– These may not guarantee the truth of their conclusions, they provide a high degree of probability for their conclusions.

– PREMISE 1:“75% of people who own iMac’s previously owned Apple IIe computers”

– PREMISE 2: “my friend has an iMac”________________________________

– CONCLUSION: “My friend owned an Apple IIe”

– Clearly invalid, but the “75%” makes it far stronger than the Bill Gates argument … (there are very few US software corp CEO’s, but 250+million US citizens!)

– Inductive invalid arguments can be stronger than valid, but unsound arguments!

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Argument Strength

Arguments

Valid Invalid

Unsound Sound Inductive Fallacious

WEAK STRONG WEAK

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CSCI102 Week 2(b)

• Thank you to Bob Brown who prepared the material for this lecture.

• Main Reference:

– Herman T. Tavani. Ethics & Technology: ethical issues in an Age of Information and Communication Technology. Hoboken, NJ: John Wiley, 2004.