A control system (2) includes hardware (111), an inter-application interference prevention processing unit (119) that operates in the hardware (111), controller applications (114) that operate on the inter-application interference prevention processing unit (119), and a selection processing unit (115). The controller applications (114) each perform a predetermined calculation on an input value and output a calculated value as a calculation result. The selection processing unit (115) selects one output value based on the calculated values outputted by the controller applications (114) and outputs the output value.