CT2 Argument Mapping (Chapter 2
Language: Meaning and Definition (2.5 …
CT2 Argument Mapping
The following claim shows the conclusion of an argument. It is presented in the form of two alternatives. Select one of the alternatives for the conclusion and write down as many arguments as possible to support that conclusion:Violent video games should/should not be banned.
Do these passages contain arguments?
If so, what is the conclusion?
There is much evidence to suggest that cannabis has therapeutic uses for people suffering from conditions such as multiple sclerosis. Given this, the prescription of cannabis should be made legal. If doctors were legally allowed to prescribe cannabis, multiple sclerosis sufferers and others might be spared much pain. Moreover, if cannabis could be legally prescribed, it would be possible to conduct large-scale surveys to establish whether cannabis really is of benefit in such cases.
Science does not provide a sufficient guide for human life, because it does not provide us with values. We need values to live our lives by.
Beliefs are like apples in a basket. One rotten apple can contaminate a whole lot of others in the same basket. Similarly, one false belief can contaminate a lot of other beliefs, and make them unjustified. I conclude that a careful thinker should question all of her beliefs to make sure none are false. (freely adapted from Descartes)
Primary school teachers should be paid better than university lecturers. The reasons for this are the following. The complex matter dealt with at universities requires students to have adequate ability in the basic skills of reading and writing. Several teachers hold that primary school teachers teach students in their most formative years, which are aptest for learning basic skills. This is why a primary school teacher’s job is more important than a university lecturer’s job. Also, people should be paid according to the contribution their job makes to society. And lastly, university lecturers are already overpaid.
chain of reasoning
- single argument
1 reason OR objection
- multiple or composite argument
more than one reason or objection
- more than 1 independent reason: convergent argument
- dependent (co-) premises
if then constructions provide arguments with a warrant: a justification why a particular premise provides support for a particular claim
- Golden Rule:
Each single argument really consists of two or more co- premises (this rule assumes that you need at least a co-premise to bridge
the gap between the major premise and the conclusion; the rule invites
you to identify minor assumptions).
- Rabbit Rule
- Holding Hands Rule
ensuring connection between premises
- conclusion + 1 reason & 1 objection
- conclusion, n+1 reasons & n+1 objections
micro-analysis of text
- conclusion markers
- premise markers
- suggestion by succession
You can also see a co-premise
as a contention that bridges the logical gap between a premise and a conclusion.
In such cases we also speak of major and minor premises. The minor premise
points at an implicit assumption needed to justify the conclusion (also see the
description of the Golden rule further on).
Argument forms: Proving Invalidity
- argument forms determines invalidity
- substitution instances of
valid argument → always valid
invalid argument → nearly always invalid, rarely valid
- only for deductive arguments
1.6 Extended Arguments
conjoint premises (geschweifte klammer)
- horizontal patterns
- vertical patterns
= dependent premisesmultiple conclusions (eckige klammer)
a group of statements, one or more of which (the premises) are claimed to provide support for, or reasons to believe, one of the others (the conclusion).
- argument forms
- hypothetical syllogism
- disjunctive syllogism
- categorical syllogism
- mathematics (not stats)
argument from authority
based on signs
if the conclusion of an inductive argument is probably true, independent of the premises, it is weak
- premises support conclusion, but not necessarily true
argument wants to prove something
- At least one of the statements must claim to present evidence or reasons.
- Th ere must be a claim that the alleged evidence supports or implies something—
that is, a claim that something follows from the alleged evidence or reasons.
- simple non-inferential passages
warnings, pieces of advice, statements of belief or opinion, loosely associated
statements, and reports
- expository passages
matter that is being dealt with is usually accepted as fact
(whether this is the case might be inferred by the type of audience)
purpose of the explanans is to shed light on, or to make sense of, the explanandum event—not to prove that it occurred. In other words, the purpose of the explanans is to show why something is the case, whereas in an argument, the purpose of the premises is to prove that something is the case
- conditional statements
We can prove the argument invalid by constructing a substitution instance having true premises and a false conclusion. We begin by isolating the form of the argument: