Summary: We examine the inseparability of mathematical reasoning and ethics by showing how mathematics is a powerful script that influences how people experience the world and act on their world. We examine four aspects of mathematics as a script: the way mathematics is used to describe social and natural phenomena; to inscribe particular values and beliefs into the way we view and understand the world; to prescribe certain actions to be taken; and how mathematics establishes a discourse that people come to subscribe to. However, by the time the numbers and measures behind mathematical descriptions are translated into actions in the real world, those values and beliefs that have been inscribed into them come obscured. The lack of transparency of the values and beliefs underpinning mathematical models raises profound ethical issues.