Question

1. Arrange this Argument properly; identifying the premises and the conclusion:

Students who sit in the front of a classroom generally earn higher grades. Therefore you should move up to the front of the class, since I know you want to improve your grade point average. (6 points)

2. In Modus Ponens Argument, why is it wrong to negate the Antecedent first and then negate the Consequent of the Proposition as the conclusion? (10 points)

3. What is the difference between Formal Fallacies and Informal Fallacies? (4 Points)

Answer 1

1. Premises are hypothetical statement from which a conclusion is drawn provided that premise assumed as true. Conclusion can be defined as judgment reached after considering the premises as true, Example: Apple is good for health is a hypothetical statement which serves as premise. People who eat apple daily will be healthy is the conclusion drawn from premise assuming that it is true.

Below are arrangement of premise and conclusion for given question:

Premise 1: Students who sit in the front of classroom generally earn higher grades. This is a claim made as hypothetical statement or condition.

Premise 2: I know you want to improve your grade point average. This is statement considered as need.

Conclusion: Therefore, you should move up to the front of class. This is a conclusion drawn considering hypothesis as true and need to be fulfilled.

2. Modus Ponens is a form argument which operates on law of affirming antecedent. Here, antecedent is actually based on previous knowledge and supported by prior conclusions. This is kind of top-down processing and it is called as forward chaining. Hence, we can say Modus Ponens is based on logic of truth.

Example: If fuel rates to go high, then people avoid using motor vehicles. Here, antecedent is higher fuel rates which is true and consequent is people avoiding the use of motor vehicles is a resultant of premise.

If we negate the antecedent for the above example, that is "fuel rates are high," then there is no logic in negating consequent. Here, the antecedent is a claim based on true value and not some mere assumption, hence making it true condition. We can only infer consequent based on antecedent and cannot negate the antecedent itself.

3. Fallacy can be defined as misconception or miss belief due to error in logic or reason.

Difference between formal fallacy and informal fallacy:

Formal fallacy is known as error in logical structure which actually in the form of structure and not in inference, whereas informal fallacy is error in inference or reason rather than structure of logic.

In formal fallacy even if premises and conclusion are true, we cannot say the conclusion is consequent of premise or antecedent. Example: Premise 1: Consuming five parts of fruits in meals will improve digestive system. Premise 2: Mr X consumes more than five parts of fruits in meals. Conclusion: Mr X is a healthy person. Here, even the premises and conclusion are true, we cannot say only those premises are reason for Mr X's healthy being. There may be other factors also.

In informal fallacy, even though argument is valid and true, there could be error in reasoning and error occur. Example: Premise: Drinking hot water is good for digestion. Conclusion: Drinking hot water will increase healthy metabolism. Here, there may be other factors affecting the metabolism like what portions of meals consumed, hygiene factor, timing, etc. We can observe here error in reasoning.