*The following appeared in a letter to the editor of the Balmer Island Gazette.*

*“The population on Balmer Island doubles during the summer months. During the summer, then, the town council of Balmer Island should decrease the maximum number of moped rentals allowed at each of the island’s six moped and bicycle rental companies from 50 per day to 30 per day. This will significantly reduce the number of summertime accidents involving mopeds and pedestrians. The neighboring island of Torseau actually saw a 50 percent reduction in moped accidents last year when Torseau’s town council enforced similar limits on moped rentals. To help reduce moped accidents, therefore, we should also enforce these limitations during the summer months.”*

Write a response in which you examine the stated and/or unstated assumptions of the argument. Be sure to explain how the argument depends on these assumptions and what the implications are for the argument if the assumptions prove unwarranted.

The proponent is arguing that if Balmer Island limits the number of moped rentals to 30 per day, the number of moped accidents will decrease. This argument rests on several questionable assumptions: first, that mopeds are only available for rent during summer months; second, that the number of moped and bicycle accidents is related; and third, that a reduction in the number of moped accidents means fewer moped and bicycle accidents. It is true that mopeds are primarily rented during the summer, but this alone does not mean that the number of moped accidents is related to the number of moped rentals.

Summertime rentals are generally limited to specific dates, and because mopeds are rented only during summer months, the town council’s decision to limit moped rentals to 30 per day will not result in a significant drop in moped accidents during the rest of the year. The rental agency’s inventory might include some mopeds that are reserved for fall or winter rentals. In addition, the rental agency may purchase new mopeds and bicycles each year, and these newer models might be rented during peak seasons.

The second assumption in the argument, that the number of moped and bicycle accidents is related to the number of moped rentals, is also questionable. Mopeds and bicycles are vehicles, and vehicles have only two speeds: forward and in reverse. If the number of mopeds increases, the number of moped and bicycle accidents may not expand proportionately, because the number of drivers may increase as well. Also, as mopeds and bicycles increase in popularity, the number of drivers will increase. The proponents of this argument suggest that the number of moped and bicycle accidents will decrease because the number of drivers will decrease, but this is not correct. The number of drivers may increase as the number of mopeds and bicycles increases, so the total number of moped and bicycle accidents may not decline.

The third assumption in the argument, that a reduction in the number of moped and bicycle accidents means fewer moped and bicycle accidents, may be valid. If the number of moped and bicycle accidents are related to the number of moped rentals, then reducing the number of moped rentals will reduce the number of moped and bicycle accidents. However, the proponents of this argument do not state that the number of accidents is related in any way to the number of moped rentals. Therefore, if the town council restricts the number of moped rentals to 30 per day, the total number of moped and bicycle accidents might actually increase.

The proponents of this argument are promoting a course of action based on false assumptions about the relationship between the number of moped rentals and moped and bicycle accidents. Their assumption that the number of moped rentals is related by the number of moped and bicycle accidents is unsupported. They assume that the number of moped rentals will decline if the number of rentals is restricted. However, restricting the number of moped rentals could have the opposite effect. If the town council restricts the number of moped rentals to 30 per day, but the number of mopeds and bicycles does not decline, the total number of moped and bicycle accidents may go up. Furthermore, it could not be assumed that the number of moped and bicycle accidents is related to the number of moped rentals. The proponents of this argument must present information about the number of moped and bicycle accidents on Balmer Island before the council can make an informed decision about the number of moped rentals.