They are non-linear dynamic. They are naturally chaotic and complex patterns. A cycle is a nail in a tire. It clicks with every revolution. Business and economies don't "cycle" because they are not round. Economic fluctuations are beautiful, natural, unique. They are not random either. Mathematics is the use of numbers to represent patterns in nature. Economic models seem cyclical only because the math and science hasn't evolved sufficiently to adequately describe the natural complexity. Instead we use approximations and oversimplified "models." Some aspects of economics seem cyclical because of our dependence on the cyclical nature of the calendar(annual reports). For many years the pattern of heartbeats was believed to be cyclical and persons who experienced "irregular" timing of heartbeats were considered at risk. We have since discovered the "fractal" or non-linear dynamic nature of heartbeats and understand that they follow a much more complex pattern that the nail in the tire.--PGSanalyst 19:43, February 23, 2008 (PST)