Presentation on theme: "Reason and Argument Chapter 1. Claims A claim takes the form of a proposition. A proposition has a similar relation to a sentence as a number does to."— Presentation transcript:
Claims A claim takes the form of a proposition. A proposition has a similar relation to a sentence as a number does to a numeral (a number is an abstraction, the numeral 2 stands for the number two) Propositions are the bearers of truth-value (if a sentence can be true or false, it expresses a proposition) and the objects of propositional attitudes (someone might believe that x or hope that x or worry that x, where x is any proposition) All claims are expressed by sentences, but not all sentences express a claim
The correspondence theory of truth A proposition is true if it reflects what is the case, and is false otherwise. The proposition expressed by the cat is on the mat is true if the cat is on the mat, and false otherwise. This is a straightforward theory of truth, and will serve perfectly well for our purposes.
Reasons and Arguments Different claims have different uses in our language. Sometimes, a claim or claims are used as a reason to believe another claim. When claims are used in this way, an argument is present. (An argument is not merely a disagreement) A claim that is used a reason for believing another claim is called a premise. The claim that is being supported in this way in an argument is the conclusion.
Arguments vs. Explanations The English word because has an ambiguous usage. Sometimes it is used in arguments, sometimes it is used in explanations. Arguments prove that a claim is the case Explanations demonstrate why or how some state of affairs came to be the case.
Standard Form Arguments are often written in a special format. Premises are numbered, and written above their conclusions: 1.Premise 1 2.Premise 2 C. Conclusion
Gainsaying the Text #1: On p.15-16, the text says arguments may have any number of premises, and that often long essays will contain arguments with many premises. Correction: an argument must have more than one premise. Also, though an argument may have indefinitely many premises, they rarely have more than 3.
Unstated premises: Sometimes an argument can appear to have only one premise. This is what happens when the person supplying the argument assumes some fact that is (usually) too obvious to be stated directly. There is usually nothing wrong with this, but in this course we will make a habit of filling in unstated premises.
Example: See pp.17-18 1.The news media are not in the business of endorsing or validating lifestyles. C. The media should not endorse lifestyles. This argument is missing the claim that people should not do what they are not in the business of doing.
Example (continued) 1.News media abandons its objectivity when it endorses lifestyles. C. News media should not endorse lifestyles. This argument is missing the claim that the news media should not abandon its objectivity.
Example (continued) 1.Endorsing lifestyles means the news media destroys what respect people have for it. C. The news media should not endorse lifestyles. Can you spot the unstated premise?
A common argument structure: 1.Statement of a particular state of affairs 2.Normative principle (contains the word should, ought, must, etc.) C. Connects the two statements in a logical way Example: 1.The new construction proposal would break the state budget 2.The state should not break its budget C. The state should reject the new construction proposal.