Forester: A pine plantation cannot successfully withstand an infestation of southern pine beetles unless the forest stand undergoes regular prescribed burning to reduce tree density. Land management records indicate that the timber tracts in the Blackwood Reserve have undergone prescribed burning on a rigorous biennial schedule for over two decades. Therefore, the Blackwood Reserve will certainly remain resilient against any southern pine beetle outbreak.
Which one of the following most accurately describes a flaw in the forester's reasoning?
- Apresumes, without presenting adequate justification, that prescribed burning has no detrimental ecological effects on other plant species in the reserve
- Bbases its conclusion on a premise that directly disputes the accuracy of documented land management records
- treats a condition that is necessary for surviving an infestation as though it were sufficient to guarantee survivalAnswer
- Dconfuses a claim used to support an intermediate finding with the main conclusion of the argument
- Eoverlooks the possibility that an environmental intervention that is beneficial in one region is invariably harmful in all other regions
Answer
The argument treats a condition that is necessary for surviving an infestation as though it were sufficient to guarantee survival.
The forester establishes that regular prescribed burning is a necessary requirement for a pine plantation to withstand beetle infestations ('cannot successfully withstand... unless...'). However, from the fact that the Blackwood Reserve has met this necessary condition, the forester concludes that the reserve is guaranteed to remain resilient. Satisfying a required condition does not guarantee the outcome, because other vulnerabilities or conditions may still lead to failure. Therefore, the argument errs by treating a necessary condition as though it were sufficient.
Step-by-Step Solution
Key Concept
Mistaking a Necessary Condition for a Sufficient Condition
Estimated Time:1m 30s