Making Reasonable Arguments
Claims and Evidence
Making Reasonable Arguments
Remember that in an argument essay
your purpose is to persuade
 In order to convince readers that your
position is correct, you need to offer
valid reasons
 Do this by:

Making reasonable claims
 Giving evidence

Making Reasonable Claims

Three kinds of claim:
Claim of fact
 Claim of value
 Claim of policy

Making Reasonable Claims

Claims of fact:
Asserts that something is, was, or will be
 Include arguments about cause and effect,
correlation, probability, and states of affairs

Making Reasonable Claims

Examples of claims of fact:
Chocolate is the most popular flavour of ice
cream for women.
 Pornography has the potential of leading to
violence.
 Capital punishment reduces crime.
 Capital punishment does not reduce crime.

Making Reasonable Claims

Claims of fact:

To support a claim of this kind you must
provide further information (evidence)
Making Reasonable Claims

Claims of value:

Concern what is right or wrong, good or
bad, better or worse than something else
Making Reasonable Claims

Examples of claims of value:
Country music deserves to be taken
seriously.
 Capital punishment is barbaric.
 Euthanasia is moral.

Making Reasonable Claims

Claims of value:

Avoid mere expressions of taste
I.e. Vanilla is better than chocolate.
 (How can one dispute this rationally?)
 But notice the difference between above
statement and “Most Canadians prefer vanilla
to chocolate,” which is a claim of fact.

Making Reasonable Claims

Claims of value:
Must go beyond expressions of taste
 May be claims of morality or claims of
artistic value
 Are usually supported by appeals to

standards
Making Reasonable Claims

Examples of claims of value with appeal
to standards:
Sex-education programs in schools are
inappropriate because aspects of moral
education should properly be given only by
parents.
 Sex-education programs in schools are
appropriate because society has a duty to
provide what most parents obviously are
reluctant to provide.

Making Reasonable Claims

In arguing a claim of value:
Be clear on the standards that you believe
support the claim
 Explain why you hold these standards
 Explain how adherence to these standards
will be of benefit

Making Reasonable Claims

Claims of policy:
Assert that a policy, law, or custom should
be initiated, altered, or dropped
 Usually characterized by words such as
“should,” “must,” and “ought”

Making Reasonable Claims

Examples of claims of policy:
Children should be allowed to vote, if they
wish to.
 A course in minority cultures ought to be
required.
 The federal tax on gasoline must be
directed toward infrastructure.

Making Reasonable Claims

In defending a claim of policy:

May begin by pointing out that there is a
problem that is usually overlooked


I.e. that suffrage for children is a matter of
children’s rights
Provide further information (evidence)

I.e. that women didn’t have the vote in Canada
until 1918 because they were considered
mentally unfit for the responsibility, an
argument which we know to be absurd
Making Reasonable Claims

In defending a claim of policy:

Consider values as well as facts

I.e. in arguing for a specific use of gasoline tax,
provide factual information about how much
money currently goes toward infrastructure,
but also argue that the allocation that you are
proposing is fairer than any other alternative
Giving Evidence

Three kinds of evidence:
Examples
 Testimony
 Statistics

Examples

Three categories of examples:
Real examples
 Invented instances
 Analogies

Examples

Real examples:

Instances that have occurred

I.e. Gun control will work. Look, for example,
at the rate of gun-related crime in the United
States.
Examples

Real examples:
Are advantageous because they are real
 Have the disadvantage of being easily
disputed


I.e. Gun violence in the U.S. is irrelevant
because we are in Canada, and our relationship
to guns is different.
Examples

Invented instances:

Are. . .invented; an instance that we can
reasonably imagine could happen

I.e. Capital punishment is bad because an
innocent person could be executed.
Examples

Invented instances:
Are advantageous because they can
present an issue clearly, free from
distracting particularities and irrelevancies
that are bound up with real examples
 Have the disadvantage of being invented;
may seem remote from the real issue
being argued

Examples

Analogies:

Comparisons pointing out several
resemblances between two rather different
things

I.e. A government is like a ship, and in times of
stress – if the ship is to weather the storm –
the authority of the captain should not be
questioned
Examples

Analogies:
Are not proof
 Are extended comparisons between two
things
 Can be useful in exposition by explaining
the unfamiliar by means of the familiar

Examples

Analogies:
Can be useful to clarify what otherwise
might be obscure
 But the usefulness of analogies can only go
so far


I.e. At the end of the day, a government is not
a ship, and the prime minister is not a captain
Testimony

Testimony is:
The citation of authorities
 Rooted in our awareness that some people
are recognized as experts

Testimony
Do not forget they you are an authority
on many things
 You may use examples from personal
experience as valid testimony

Testimony

Used for two reasons:
Expert opinion carries weight with an
audience
 A change of voice (if the testimony is not
your own) is enjoyable for the reader

Testimony

Testimonial downsides:
Words of an expert may be taken out of
context or otherwise distorted
 Authorities may not be authorities on the
present topic


I.e. Don’t use the words of David Suzuki to
argue one side or the other of the abortion
debate
Statistics

Are especially useful in arguments
concerning social issues

I.e. If we are arguing to raise the driving
age, we will look up statistics about the
number of accidents cause by people in
certain age groups
Statistics

Have the disadvantage of opening your
argument to dispute from the other side

The significance of statistics can be difficult to
assess


I.e. opponents of gun control legislation in Florida
cited a statistic that showed that gun violence
increased after enactment of the law.
Supporters of gun control pointed out that in the
years following the enactment of the law Miami
became the cocaine trafficking capital of the U.S.,
and the increase of drug trade, not gun control
laws, resulted in a higher rate of gun violence
Giving Evidence

Use evidence from:
Your own experience
 Your reading
 Your talks with others


Examples:
Clarify and support your assertions
 Help make the abstract concrete

Giving Evidence

How much evidence is enough?
Put yourself in your readers’ shoes
 Generally a single example may not fully
illuminate a difficult point
 More than two examples are often
unnecessary

Giving Evidence
It is not possible to argue an airtight
case on most issues
 It is your job to offer a reasonable
argument
 (and don’t forget to acknowledge
possible reasonable counterarguments!)
