Quote:
The following appeared in the summary of a study on headaches suffered by the residents of Mentia.
"Salicylates are members of the same chemical family as aspirin, a medicine used to treat headaches. Although many foods are naturally rich in salicylates, for the past several decades, food-processing companies have also been adding salicylates to foods as preservatives. This rise in the commercial use of salicylates has been found to correlate with a steady decline in the average number of headaches reported by participants in our twenty-year study. Recently, food-processing companies have found that salicylates can also be used as flavor additives for foods. With this new use for salicylates, we can expect a continued steady decline in the number of headaches suffered by the average citizen of Mentia."
Write a response in which you discuss what specific evidence is needed to evaluate the argument and explain how the evidence would weaken or strengthen the argument.
The report predicts that the average citizen of Mentia will experience a decline in the number of headaches, citing facts about salicylates and their use by foods-processing companies. However, it would be far too hasty to accept this prediction as fact. The report's chain of logic is utterly incomplete; a litany of additional evidence is needed before we can determine whether or not the study's arguments hold water.
To begin, the main thrust of the report's argument is the assumption that salicylates are effective at reducing headaches, but it doesn't provide enough evidence to conclusively demonstrate this fact. The report mentions that salicylates are members of the same chemical family as aspirin; however, it doesn't go far enough to indicate that the similarities between aspirin and salicylates imply that they have similar headache-reducing effects. We need more information about the specific chemicals shared between the two substances. For example, if we discovered that the active ingredient in aspirin is NOT actually present in salicylates, then the report's argument is significantly weakened. Moreover, the report claims that increased use of salicylates in foods was found to be correlated with a decline in reported headaches. Yet, correlation doesn't necessarily imply causation; we need more evidence to rule out alternative explanations for this trend. Perhaps over the study's time frame, there was a decrease in air pollution that mitigated headaches, or perhaps the subjects in the study participated in a newly popular exercise program that had a side-effect of reducing headaches. In these cases, the study's results become far less reliable, and we can't conclude that salicylates reduce headaches. Given how important this assumption is to the report's overall argument, more evidence is desparately needed before we can accept the report's prediction as fact.
Even if the report's claim that the increased use of salicylates in foods as a preservative directly caused the number of headaches to decrease turns out to be true, it would still not be enough to conclude that using salicylates as a flavor additive would also have the same effect. After all, introducing the substance in a new context could drastically change its effects. Perhaps using salicylates as a flavor additive involves adding it in an earlier stage of the food-processing procedure, causing its headache-reducing compounds to be destroyed. Or perhaps using salicylates as both a preservative AND a flavor additive causes the headache-reducting effects to cancel out, leading to MORE headaches. In order to determine whether this new policy would have a similar effect, we need more information, perhaps in the form of scientific studies, about the effects of salicylates as a flavor additive specifically.
Moreover, we don't even know whether of not food-processing companies will actually implement this new use of salicylates. Although the report states that companies have "found" it, it is possible that this technique is extremely expensive, or requires new, complicated machines, meaning that the cost of implementing it doesn't justify the benefits. In this case, there won't actually be an increase in the presence of salicylates in food, completely undermining the report's conclusion. Thus, we should collect evidence to determine whether companies will actually follow through with the inclusion of salicylates as a flavor additive.
Finally, the report doesn't include any evidence specific to the city of Mentia. It is possible that, for example, the citizens of Mentia don't consume any foods produced by food-processing companies that use salicylates. In this case, none of the report's arguments are relevant to its prediction, and its logic falls apart. Thus, it is vital to gather information regarding how representative the evidence presented in the report is of the the average citizen in Mentia.
In summary, before we determine the veracity of the report's prediction, we need a great deal of additional evidence. As it stands, we don't know nearly enough to conclude that the average citizen in Mentia will truly experience fewer headaches due to an increased use of salicylates.