Reasoning and Argument Analysis

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Reasoning and Argument Analysis
Clark Wolf Director of Bioethics Iowa State
University jwcwolf_at_iastate.edu
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• OBJECTIVES On completion of this unit, students
  should be able
• 1.1 to recognize when they are presented with an
  argument,
• 1.2 to analyze arguments by identifying the
  conclusion and distinguishing conclusions from
  premises.
• 1.3 to evaluate arguments by considering the
  plausibility of the premises and the extent to
  which the premises support the conclusion.
• 1.4 to distinguish deductive and inductive
  arguments,
• 1.5 to distinguish an arguments content from
  its form.
• 1.5 to define key concepts argument, premise,
  conclusion, evidence, rationally persuasive
  argument, fallacy, valid argument, invalid
  argument, inductive argument, abductive argument.
  
• 1.6 to evaluate arguments, by (i)
  distinguishing premises from conclusion, (ii)
  putting the argument in standard form, (iii)
  critically examining the premises, and (iv)
  evaluating the inference from premises to
  conclusion.
• 1.7 to be self-reflectively critical of their
  own arguments and those of others.

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What is an Argument?

• Argument A set of statements, some of which
  serve as premises, one of which serves as a
  conclusion, such that the premises purport to
  give evidence for the conclusion.
• Premise A premise is a statement that purports
  to give evidence for the conclusion.
• Evidence To say that a statement A is evidence
  for another statement B is to say that if A were
  true, this would provide some reason to believe
  that B is true.
• Conclusion The statement in an argument that is
  supposedly supported by the evidence.

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When do we encounter arguments?

• Any time anyone tries to persuade you of
  something, or to make you change your mind.
• Rational persuasion uses reasons, but even
  irrational persuasion employs reasons (bad
  reasons). In evaluating arguments, we need to be
  able to evaluate reasons and patterns of
  reasoning.

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Indicator Words

• Indicator words Sometimes writers use language
  that indicates the structure of the argument they
  are giving. The following words and phrases
  indicate that what follows is probably the
  conclusion of an argument
• Therefore
• thus
• for that reason
• hence
• it follows that

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Conclusion Indicators

• Because
• Since
• For
• For the reason that

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Example

• Because animals are conscious, capable of
  experiencing pain and pleasure, they are like
  people in significant respects. Since they are
  also intelligentoften far more intelligent than
  newborn babies for example, it follows that they
  deserve kind treatment from human beings and that
  it is wrong to treat them with cruelty.

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Examples

• Since private business is the most effective
  instrument of economic change, the government
  should utilize the resources of private business
  in its economic planning and decision making.
• Women work just as hard as men and are just as
  productive. Therefore they should be compensated
  the same.

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Standard Form

• Standard Form Usually we find arguments
  expressed in ordinary prose. But as noted, when
  we are evaluating arguments it is a good idea to
  separate the premises from the conclusion, and to
  put the argument into standard form. We say
  that an argument is in standard form when the
  premises are numbered and listed separately, and
  when the conclusion is clearly written underneath
  them.

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Standard Form Version

• (1) Animals are conscious.
• (2) Animals are capable of experiencing pain and
  pleasure.
• (3) Animals are intelligent.
• (4) Animals are like people in significant
  respects.
• Conclusion
• (5) Therefore (i) animals deserve kind treatment
  from humans and (ii) it is wrong to treat animals
  with cruelty.

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A Reservation

• Whenever we put an argument in standard form, we
  have given an interpretation of that argument.
  Ideally, an interpretation should accurately
  capture the meaning of the original, but it is
  always possible to challenge the accuracy of an
  interpretation.

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Evaluating an Argument

• By splicing genes into crop plants, scientists
  have changed these crops in ways that never could
  have come about through the natural process of
  selective breeding. These changes in our food
  crops threaten the health of everyone in the
  world, and impose a great danger of massive
  environmental damage. Genetically modified crops
  are unnatural and dangerous. We should avoid
  using them and growing them, and should do
  whatever it takes to eliminate them from Iowa
  farms.

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Questions

• What is the author of this passage trying to
  persuade you to believe? (Whats the
  conclusion?)
• What reasons are being offered? (What are the
  premises?)
• In this argument there are few indicator words
  used, but it is not hard to figure out what the
  author would like us to believe.

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Whats the Conclusion?

• Conclusion Often the conclusion of an argument
  is stated either in the first sentence of a
  paragraph, or in the last sentence of the
  paragraph. In this case, the conclusionthe
  claim the author intends to persuade us to
  acceptis a complex claim. The author urges
  that
• (1) We should avoid using and growing genetically
  modified crops, and
• (2) We should do whatever it takes to eliminate
  these crops from Iowa farms.

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Whats evidence or reasons are given?

• Premises
• P1) Gene splicing changes crops in ways that
  could never have come about through selective
  breeding.
• P2) Changes in food crops due to gene splicing
  threaten everyones health.
• P3) Changes in food crops pose a threat of
  massive environmental damage.
• P4) Genetic modification of crops is unnatural.
• P5) Genetic modification of crops is dangerous.

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Step One Are the premises true?

• Premise 1 Gene splicing changes crops in ways
  that never could have come about through
  selective breeding.
• Evaluation Is this true? Some of the properties
  that have been induced through genetic
  engineering might have been produced through
  selective breeding. But it is unlikely that the
  genetic alterations that have been effected in
  the production of genetically modified crops
  would have been produced in any other way.
  Perhaps this premise should be somewhat
  qualified, but it contains a kernel of truth.

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Step One Are the premises true?

• Premise 2 Changes in food crops due to gene
  splicing threaten everyones health.
• Evaluation This claim requires additional
  support and evidence. Many people are concerned
  about the health effects of genetically modified
  food crops, but no one has shown that these crops
  are dangerous. The author of the paragraph
  provides no evidence that genetically modified
  crops are dangerous.

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Step One Are the premises true?

• Premise 3 Changes in food crops pose a threat of
  massive environmental damage.
• Evaluation Once again, this claim requires
  support. There may indeed be reasons for concern
  about the environmental effects of genetically
  modified crops, but the author has not given us
  any evidence. Without more evidence, we may not
  be in a position to evaluate this premise.

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Step One Are the premises true?

• Premise 4 Genetic modification of crops is
  unnatural.
• Evaluation The term natural can be slippery,
  and we may need to know more about what the
  author has in mind. In context, it seems that
  the author regards things that are unnatural as
  bad. But in an important sense, bridges,
  computers, vaccines and artworks are unnatural.

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Step One Are the premises true?

• Premise 5 Genetic modification of crops is
  dangerous.
• Evaluation Once again we need evidence for such
  a claim before we can place our trust in it. In
  what sense is genetic modification dangerous, and
  what are the specific dangers the author has in
  mind? Without more evidence, we may simply find
  that we are not yet in a position to evaluate the
  argument.

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• Step Two
• If the premises were true, would they provide
  good evidence for the conclusions?
• Are there implicit premises that should be
  included in the evaluation of the argument?

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• A Strategy for Evaluating Arguments Of course,
  for the purposes of this course, your views about
  GM crops are not what matter. What does matter
  is the strategy used here for evaluating the
  argument under consideration
• First, identify the arguments premises, and
  restate them clearly.
• Second, evaluate each premise individually is it
  true or false? What evidence, what information
  would you need to know in order to determine
  whether the premises are true?
• If you discover that the premises of the argument
  are simply false, you may need to go no further.
  But if the premises seem true, there is a third
  important step to take in evaluating the
  argument
• Third, consider the relationship between the
  premises and the conclusion. What kind of
  argument is it? Is it a good argument of its
  kind?

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Fallacies

• Fallacy An argument that provides the illusion
  of support, but no real support, for its
  conclusion.

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Evaluating Philosophical Arguments

• Fair-Mindedness and the State of Suspended
  Judgment When evaluating arguments, we should
  strive to be impartial and fair-minded. We
  should try to follow where the best reasons lead
  instead of pre-judging the conclusion.

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• Argument for Analysis
• There is no universal standard for right and
  wrong. Different people simply have different
  views and different values. None of us is in a
  position to say that our values or our moral
  judgments are privileged, or that they are
  uniquely better than the judgments of others.

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What do we learn from the Bloggs Cases?
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Ethical Theory

• We reveal our ethical views when we explain or
  justify our choices and behavior to others.
• Ethical views can be thoughtless and
  unreflective, or thoughtful and reflective. To
  the extent that were thoughtless and
  unreflective, our value system will lack
  integrity and depth.
• If our values are shallow and incoherent, we will
  make bad decisions, and we will be shallow and
  incoherent. (?)

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Stop here ON TO PLATO!
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Reasoning in Ethics

• Rachels notes that philosophy is not like
  physics. In physics, there is a large body of
  established truth, which no competent physicist
  would dispute and which beginners must patiently
  master. (Physics instructors rarely invite
  undergraduates to make up their own minds about
  the laws of thermodynamics.) (ix-x)

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Reasoning in Ethics

• 1.1 The Problem of Definition A theory of
  morality is a theory about how we should live and
  why. It turns out to be impossible to give a
  simple definition of morality. This should
  make us cautious, but shouldnt dissuade us from
  investigating the subject further. In this book
  we will examine alternative theories of morality,
  consider the reasons that support or oppose each
  of them, and come to evaluative judgments.

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Reasoning in Ethics

• What is the Minimal Conception of Morality that
  Rachels offers? Is it as minimal as he thinks?
• Do we need a common minimum before we can reason
  about moral questions?

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• Bloggs Cases

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Moral Theory

• Metaethics What is morality? Where does moral
  value come from?
• Normative ethics What principles identify right
  and wrong conduct?
• Applied/practical ethics What are the salient
  ethical considerations in evaluating specific
  practices, actions, or technologies?

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Bloggs Case 1
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Bloggs Case 1

• Utilitarianism The ethical thing to do is that
  which maximizes aggregate benefit for everyone.
• The common good

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Bloggs Case 2
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Rights

• Would slicing and dicing Bloggs violate his
  rights? (What are rights?)
• A person has a right just in case our obligations
  toward her are based on the effect that our
  treatment will have on her, not on others.
• Animals have rights just in case our obligation
  to treat them humanely are based on the effect
  that this treatment would have on the animals
  themselves, not the effect it would have on other
  people.

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Bloggs Case 2

• Response Slicing and dicing Bloggs would violate
  his rights.
• A moral right is a justified claim that an
  individual (or group) may make to certain objects
  or certain treatment by others.
• Bloggss right to X may take the form of
• A claim that Bloggs may make to a particular
  object (e.g., his kidneys)
• A constraint on how Bloggs should be treated
  (e.g., he shouldnt be killed for his organs)
• An obligation on others not to interfere with
  Bloggss doing X (e.g., his continuing to live)

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Ethical Theory

• Kant Categorical Imperative
• Act only such that you could will the maxim on
  which you act as a universal law.
• Act so that you treat humanity, whether in your
  own person or that of another, always as an end
  in itself, and never as a means only.
• Would slicing and dicing Bloggs for his organs
  involve treating him as a mere means?

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Ethical Theory

• Killing v. Letting Die It has sometimes been
  argued that we have a moral duty not to kill, but
  no moral duty (or a lighter moral duty) not to
  let people die.
• Does this distinction explain why we shouldnt
  kill Bloggs for his organs?

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Bloggs Case 3
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Bloggs Case 3

• The ethics of acts vs. omissions
• The greater good vs. clean hands

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Ethical Theory

• We reveal our ethical views when we explain or
  justify our choices and behavior to others.
• Ethical views can be thoughtless and
  unreflective, or thoughtful and reflective. To
  the extent that were thoughtless and
  unreflective, our value system will lack
  integrity and depth.
• If our values are shallow and incoherent, we will
  make bad decisions, and we will be shallow and
  incoherent. (?)

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• Fini.

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Rachels Examples

• Baby Theresa
• Jodie and Mary
• Tracy Lattimer Case
• Case of Fauziua Kassindja

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What should we glean from these cases?

1. Some Basic Moral Considerations Benefit to
   others, Do no harm, Sanctity of life, truth
   telling, etc.
2. Is there a basic common moral minimum?
3. Moral judgments have reasons they are supported
   by our beliefs, and by lines of reasoning.
   Therefore we can critically evaluate our moral
   judgments using the tools of argument analysis.

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• Moral Reasoning Whether we agree about the
  verdicts in these cases or not, we can agree that
  our moral judgments are based on reasons, that we
  can articulate these reasons and evaluate them,
  that we can examine how competing reasons
  interact with one another. Morality is therefore
  about reasoning, not just about reasonless or
  intuitive judging.
• Requirement of Impartiality This, according to
  Rachels, is the idea that every persons
  interests are equally important from the moral
  point of view. Impartiality of this sort is a
  commitment.

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Next Deductive Argumentsand Moral Relativism

• Deductive Argument An argument that has the
  property that if the premises are true, then the
  conclusion cannot be false.
• Example
• All vertibrates have hip bones.
• Snakes are vertibrates.
• Therefore, snakes have hipbones.

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Cultural Relativism

• There is no universal standard for right and
  wrong. Different people simply have different
  views and different values. None of us is in a
  position to say that our values or our moral
  judgments are privileged, or that they are
  uniquely better than the judgments of others.

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• We will not cease from exploration
• And the end of our exploring
• Will be to arrive where we started
• And know the place for the first time.
• --T.S. Eliot, Four Quartets

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• An Argument for Analysis
• All loyal Americans should proudly vote for
  George Bush in the upcoming election. In times
  of crisis, we should avoid loosing face before
  the world community by voting a proven leader out
  of office. George Bush has shown that he can
  make decisive and forceful decisions, and his
  efforts in Afghanistan and Iraq have earned him
  the respect of the American people, and of our
  allies overseas. It is unthinkable that we might
  vote such a leader out of office.

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• Argument for Analysis
• Only by replacing Bush can we hope for a peaceful
  exit for our troops in Iraq and Afghanistan.
  Because the Iraqui and Afghan people regard US
  troops as conquering invaders, they hate our
  soldiers and take every opportunity to harm and
  abuse them. Because of this, US troops are
  uniquely ill-suited to bring order and stability
  to these war torn nations. Only an international
  force could gain the trust of the people of Iraq
  and Afghanistan, and only a force that gains
  their trust can maintain stability and peace.
  But George Bush has squandered the good will of
  the international community, and it is unlikely
  that any international force will help us while
  he is in office.