Syllogisms Deductive Reasoning Remember There Is A Differenc

Syllogisms Deductive Reasoningremember There Is A Difference Between

Analyzing syllogisms involves understanding the structure of deductive reasoning and distinguishing between valid logical form and the truth of premises. A syllogism comprises major and minor premises leading to a conclusion, with specific terms: the major term, minor term, and middle term. Validity depends on the form, while soundness depends on the truth of the premises. Recognizing logical errors such as equivocation—using a word with different meanings—also plays a crucial role in evaluating arguments.

This essay examines five syllogisms, identifies their premises and terms, evaluates their validity based on form and reasoning, and discusses potential logical fallacies or strengths. Using diagrams and logical analysis, we assess whether the conclusions logically follow from the premises, independent of whether the premises are true.

Paper For Above instruction

Syllogism 1: "All human societies are doomed to deteriorate over time. America is a human society. Snails are cold-blooded things. Confucius is a human. America is doomed to deteriorate over time."

Major Premise: All human societies are doomed to deteriorate over time.

Minor Premise: America is a human society.

Conclusion: America is doomed to deteriorate over time.

Major Term: Deteriorate over time

Minor Term: America

Middle Term: Human societies

This syllogism is valid in form, following Barbara categorical syllogism structure. The conclusion logically follows if the premises are true. The validity hinges on the form rather than the truth of premises. No invalid logical steps are present, and the middle term correctly connects the major and minor premises, making this a valid syllogism.

Syllogism 2: "No philosophers are evil. All Greeks are philosophers. No Greeks are evil."

Major Premise: No philosophers are evil.

Minor Premise: All Greeks are philosophers.

Conclusion: No Greeks are evil.

Major Term: Evil

Minor Term: Greeks

Middle Term: Philosophers

This syllogism is valid in form, following the Mood EAE. The universal negative major premise and universal affirmative minor premise lead to a valid conclusion. The reasoning correctly distributes the terms, and the conclusion follows necessarily if premises are true, confirming formal validity.

Syllogism 3: "All women are potential mothers. Betty is a potential mother. Betty is a woman."

Major Premise: All women are potential mothers.

Minor Premise: Betty is a potential mother.

Conclusion: Betty is a woman.

Major Term: Women

Minor Term: Betty

Middle Term: Potential mother

This syllogism is invalid because the conclusion "Betty is a woman" does not necessarily follow from the premises. The premises establish that all women are potential mothers and Betty is a potential mother, but Betty might not be a woman—she could be a potential mother who is not a woman (e.g., an animal, metaphorically). The error lies in assuming the converse, leading to affirming the consequent, which is a logical fallacy.

Syllogism 4: "All students are eligible for student government. No teachers are eligible for student government. No teachers are students."

Major Premise: All students are eligible for student government.

Minor Premise: No teachers are eligible for student government.

Conclusion: No teachers are students.

Major Term: Students

Minor Term: Teachers

Middle Term: Eligibility for student government

This syllogism is invalid due to the fallacy of the undistributed middle. While the premises suggest teachers are outside the category of students due to eligibility, the conclusion that teachers are not students does not necessarily follow from the premises. The correct conclusion should be "No teachers are eligible for student government," which is supported, but not necessarily that teachers are outside the student category, unless explicitly stated. The logical error results from improper inference.

Syllogism 5: "All barbiturates are drugs. Marijuana is not a barbiturate. Marijuana is not a drug."

Major Premise: All barbiturates are drugs.

Minor Premise: Marijuana is not a barbiturate.

Conclusion: Marijuana is not a drug.

Major Term: Drugs

Minor Term: Marijuana

Middle Term: Barbiturates

This is an invalid syllogism because the conclusion that "Marijuana is not a drug" does not logically follow from the premises. The premises only specify that marijuana is not a barbiturate, but it could still be a drug outside the category of barbiturates. The logical fallacy here is denying the consequent—assuming that the absence from one category implies absence from the broader category. The valid form would require additional premises addressing whether marijuana falls under drugs in general.

References

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