Behind this is the idea that it is possible to see the world in multiple ways, and that there is not one fair method to see which way is right. Some think that scientific traditions (or "paradigms") can be incommensurable: it is not really possible to say which one is right. This idea has been defended by Thomas Kuhn. He wrote: "when paradigms change, the world changes with them". Paul Feyerabend was another philosopher who said that incommensurability was possible in scientific topics. He wrote that it is important to remember this, because it means that it is possible to say things that are not scientific, but also not wrong. These ideas were mainly aimed at Karl Popper and his ideas on falsification.