In an attempt to improve highway safety, Prunty County last year lowered its speed limit from 55 to 45 miles per hour on all county highways. But this effort has failed: the number of accidents has not decreased, and, based on reports by the highway patrol, many drivers are exceeding the speed limit. Prunty County should instead undertake the same kind of road improvement project that Butler County completed five years ago: increasing lane widths, resurfacing rough highways, and improving visibility at dangerous intersections. Today, major Butler County roads still have a 55 mph speed limit, yet there were 25 percent fewer reported accidents in Butler County this past year than there were five years ago.
One might dispute whether psychological egoism is any more parsimonious than psychological altruism (Sober & Wilson 1998, pp. 292-3). More importantly, however, it is no argument for a view that it is simpler than its competitors. Perhaps we might employ Ockham’s Razor as a sort of tie-breaker to adjudicate between two theories when they are equal in all other respects, but this involves more than just simplicity (Sober & Wilson 1998, pp. 293-5). As David Hume puts it, psychological egoism shouldn’t be based solely on “that love of simplicity which has been the source of much false reasoning in philosophy” (1751/1998, p. 166). The heart of the debate then is whether there are other reasons to prefer one view over the other.