The following appeared in a letter to the school board in the town of Centerville. "All students should be required to take the driver's education course at Centerville High School. In the past two years several accidents in and around Centerville have in

This letter recommends mandatory driver's education courses at Centerville High School. The author bases this recommendation on three facts: during the last two years several Centerville car accidents have involved teenage drivers; Centerville parents are too busy to teach driving to their children; and the two private driver-education courses in the area are expensive. As discussed below, the argument suffers from several critical flaws and is therefore unpersuasive.

First of all, the letter fails to indicate who or what caused the car accidents to which the letter refers. If Centerville High School students caused the accidents, and if those accidents would have been avoided had these students enrolled in the high school's driving course, then the argument would have merit. However, it is equally likely that the other drivers were at fault, or that no driver was at fault. Moreover, it is entirely possible that the teenage drivers had in fact taken the high school's driving course, or that they were not local high school students in the first place. The author must rule out all these possibilities in order to conclude confidently that a school-sponsored mandatory driving course would have prevented these accidents.

Secondly, whether the fact that several car accidents the last two years involved teenage drivers suggests a need for a mandatory driving course depends partly on the comparative accident rate during earlier years. It is entirely possible, for instance, that the rate of accidents involving teenagers has been steadily declining, and that this decline is due to the availability of the two private driving courses. Without ruling out this possibility, the letter's conclusion is not defensible.

The argument is problematic in certain other respects as well. It assumes that a mandatory school-sponsored course would be effective, yet provides no evidence to support this assumption. Similarly, the argument fails to substantiate its assumption that a significant percentage of Centerville's parents cannot afford private driving instruction for their teenage children. Absent substantiating evidence for either of these necessary assumptions, I cannot be convinced that Centerville should establish the proposed driving course.

In conclusion, the letter's author fails to adequately support the recommendation for a school-sponsored mandatory driving course. To strengthen the argument, the author must provide clear evidence that Centerville High School students caused the accidents in question, and that a mandatory driving course would have prevented them. To better evaluate the argument, I would need more information about the affordability of the two private driving courses and about the effectiveness of a mandatory school-sponsored course compared to that of the two private courses.