In Logic types of fallacy are firmly described thus: First the premises and the conclusion must be statements, capable of being true or false. Secondly it must be asserted that the conclusion follows from the premises. In English the words therefore , so , because and hence typically separate the premises from the conclusion of an argument, but this is not necessarily so. Thus: Socrates is a man, all men are mortal therefore Socrates is mortal is clearly an argument (a valid one at that), because it is clear it is asserted that Socrates is mortal follows from the preceding statements. However I was thirsty and therefore I drank is NOT an argument, despite its appearance. It is not being claimed that I drank is logically entailed by I was thirsty . The therefore in this sentence indicates for that reason not it follows that .
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.