Philosophy Informal Logic Questions Long
The main types of informal fallacies based on deduction are as follows:
1. Affirming the consequent: This fallacy occurs when someone assumes that if a statement is true, then its consequent must also be true. For example, "If it is raining, then the ground is wet. The ground is wet, therefore it must be raining." This reasoning is flawed because there could be other reasons for the ground being wet, such as a sprinkler system.
2. Denying the antecedent: This fallacy occurs when someone assumes that if a statement is false, then its antecedent must also be false. For example, "If it is raining, then the ground is wet. It is not raining, therefore the ground must not be wet." This reasoning is flawed because there could be other reasons for the ground being wet, such as a recent rainstorm.
3. Fallacy of composition: This fallacy occurs when someone assumes that what is true of the parts must also be true of the whole. For example, "Each brick in this wall is lightweight, therefore the entire wall must be lightweight." This reasoning is flawed because the properties of individual parts do not necessarily apply to the whole.
4. Fallacy of division: This fallacy occurs when someone assumes that what is true of the whole must also be true of its parts. For example, "This car is expensive, therefore each individual part of the car must be expensive." This reasoning is flawed because the value of the whole does not necessarily determine the value of its individual components.
5. False dilemma: This fallacy occurs when someone presents a situation as having only two possible options, when in reality there are more alternatives. For example, "Either you support this policy, or you are against progress." This reasoning is flawed because it ignores the possibility of other options or alternative solutions.
6. Begging the question: This fallacy occurs when someone assumes the truth of the conclusion in the premises. For example, "God exists because the Bible says so, and the Bible is true because it is the word of God." This reasoning is flawed because it assumes the existence of God in order to prove the existence of God.
These are some of the main types of informal fallacies based on deduction. It is important to recognize and avoid these fallacies in order to engage in logical and rational reasoning.