The reason why a currency’s independence in pairs is easy to see is because, when a trader compares one currency to another, and brings in a third currency, it becomes evident that the currency must be somewhat correlated to one if not both of the other currency pairs. The trader also needs to realize that the interdependence among currencies comes from much more than the simple fact that they are in pairs, where some currency pairs move in a repetitive cycle, other currency pairs may repel, due to external, complex forces.