Explanation
The argument commits a logical fallacy by assuming that reversion to barter systems in the absence of currency is evidence of the original economic system. This is a circular argument because it uses what it is trying to prove (that barter was the first economic system) as evidence for its conclusion.
A. The argument does not simply state that barter is necessary for the development of currency; it claims that barter was the original system because economies revert to it when currency is absent. This choice misidentifies the type of flaw, as the argument's issue is not about necessity leading to a particular outcome but about assuming historical reversion implies original practice.
B. There is no apparent internal contradiction in the premises. All the premises point in the same direction, which is towards the conclusion that barter systems must have been the original form of economic exchange. The incorrectness lies not in contradiction but in the argument's circular nature.
C. The argument does not make a normative claim about what should be done based on historical precedent; rather, it makes a historical claim about what was done. Therefore, the flaw is not in presuming a course of action but in the logic used to interpret historical patterns.
D. While the argument does infer causation (barter as the original system) from a sequence of events (reversion to barter in the absence of currency), the fundamental flaw isn't merely the temporal connection but the way the argument takes a historical reversion to imply an original condition without justification.
E. (Correct Response) The argument is circular because it relies on a premise that assumes the conclusion. It suggests that because economies revert to barter when there is no currency, barter must have been the original economic system. However, this premise is essentially the conclusion in a different guise, as the "original economic system" is inferred directly from the behavior of economies in the absence of currency, without independent evidence.
The flaw identified in option E is that the argument is reasoning in a circle: it starts with what it is trying to end with, assuming the originality of barter based on the very pattern it cites as evidence for that originality.