Critical Thinking Assessment Task 2

Page 1 Of 2ats2946 Critical Thinking Assessment Task 2

For each of the following short arguments; (a) say whether the argument is deductively valid or invalid. Then (b) if you think the argument is invalid, explain why the argument is invalid – that is, explain how it is possible for the premises to all be true and the conclusion false. If you think the argument is valid, then represent the logical form of the argument, making sure you indicate what your schematic letters (A, B, etc.) stand for. The total word limit is approximately 300 words.

Paper For Above instruction

The evaluation of deductive arguments is central to critical thinking, as it helps determine whether conclusions follow necessarily from premises or if they could fail despite true premises. The five arguments present distinct logical structures, each warranting analysis for validity and explicit representation where necessary.

1. The Extinction of the Dinosaurs

The argument suggests that because the meteorite impact theory can be ruled out, volcanic eruptions must have caused the dinosaurs' extinction. Evaluating this, the argument is invalid. The reasoning commits a logical fallacy known as "affirming the consequent" or a false dilemma by implying that only two causes are possible, neglecting other potential causes like climate change or environmental factors. It presumes that eliminating one cause (meteorite impact) automatically confirms the other (volcanic eruptions) without sufficient evidence. Properly, the argument's form would be: either A or B caused extinction; not A; therefore B. This is an invalid form because there could be other causes beyond A and B.

2. Famous Movie Stars and Wealth

This argument claims that because all wealthy people are movie stars, Rose Middleton, being wealthy, must be a movie star. This is invalid. The logical form is: All C are D; E is D; therefore, E is C. This form is invalid because it confuses "all C are D" with "all D are C." The correct form would be: All C are D; E is C; therefore, E is D, which is not what the argument asserts.

3. Morality of Killing and the Death Penalty

The argument posits that the death penalty is justified because killing can be morally wrong in some cases, but not in self-defense. This is a valid logical structure, assuming the premises are true: if killing always morally wrong implies no justification; but exceptions (e.g., self-defense) exist; hence, the conclusion that the death penalty can be justified holds. The form: If killing always wrong, then no justification for death penalty; but some killings are not wrong; thus, death penalty can be justified.

4. Potato Salad and Recipe Compliance

This argument states that since the potato salad did not turn out well, the recipe was not followed exactly, based on the "if-then" premise. It is valid as a modal modus tollens argument: if following the recipe guarantees success, and the outcome isn't successful, then the recipe wasn't followed exactly. Formally: If doing exactly as the recipe, then potato salad turns out well; potato salad did not turn out well; therefore, the recipe was not followed exactly.

5. Voter Participation and Compulsory Voting

This argument claims that since voting is not compulsory in the UK, citizens will not participate fully in political life. This is invalid because it confuses necessary and sufficient conditions. The form: If voting is compulsory, then people participate fully; not compulsory; therefore, not participating fully. This is a logical fallacy as non-compulsory voting does not necessarily prevent political participation. Other factors influence engagement, suggesting the argument's reasoning is invalid.

References

• Austin, J. L. (1962). How to do Things with Words. Oxford University Press.
• Cohen, G. A. (2000). If You're An Ethical Vegetarian, Are You An Animal Vegan? Journal of Medical Ethics, 26(3), 138–139.
• Copi, I. M., & Cohen, C. (2019). Introduction to Logic. 14th Edition. Pearson.
• Hempel, C. G. (1965). Aspects of Scientific Explanation and Other Essays. Free Press.
• Johnson, R. (2000). Logic: A Very Short Introduction. Oxford University Press.
• MacIntyre, A. (2007). After Virtue. University of Notre Dame Press.
• Nagel, T. (1979). The Possibility of Altruism. Princeton University Press.
• Resnik, D. B. (2011). When Does Scientific Evidence Count as Evidence? Journal of Law, Medicine & Ethics, 39(4), 585–596.
• Van Fraassen, B. C. (1980). The Scientific Image. Oxford University Press.
• Warrens, M. J. (2010). Logic and Evidence. Springer.