Consilience requires the use of independent methods of measurement, meaning that the methods have few shared characteristics. That is, the mechanism by which the measurement is made is different; each method is dependent on an unrelated natural phenomenon. For example, the accuracy of laser rangefinding measurements is based on the scientific understanding of lasers, while satellite pictures and meter sticks rely on different phenomena. Because the methods are independent, when one of several methods is in error, it is very unlikely to be in error in the "same way" as any of the other methods, and a difference between the measurements will be observed. If the scientific understanding of the properties of lasers were inaccurate, then the laser measurement would be inaccurate but the others would not.