The Straight Line: A rather mundane consideration at first glance. If you want a straight line, simply get a ruler and a pencil and presto! We have achieved our goal! This is of course, partly true, but it is by no means the whole picture. Consider sports, such as archery or marksman shooting. Here the accuracy of the sport is measured in terms of precision and consistency of the line produced by the archer (or marksman) and his instrument. These activities, and others like them, have been a source of human interest for centuries. And, it would be fair to point out, that in actual practice even these lines are not actually straight because of the variation caused by distance and gravity (parabola). Thus, the archer will aim a little above the centre mark to allow the arrow to rise and fall and take into account gravity, distance, and speed. The rifle bullet, especially at relatively short distances, is closer to an ideal straight line than the archer. The important point (!) here is that there are many human activities in both sport and science that are contingent on our ability to produce and reproduce this rather singular, and apparently simple phenomena. So it is not altogether surprising that at the very center of Billiards practice we find the notion of “the straight line” emphasized as being the first and foremost organizing principle.
