A “paradigm” is a way of interpreting and making sense of the world. As such, our views on soil fertility are coherent with our interpretation of the scientific process and science institutions, and perhaps our feeling about the place of agriculture in the larger scheme of things. In agriculture today, two contradictory approaches to soil fertility uneasily coexist – the cation ratio paradigm (CR) and that referred to as “sufficient level of available nutrients” (SLAN).