text: Hindrance to the perceptions of sense is an evil to the animal nature. Hindrance to the movements (desires) is equally an evil to the animal nature. And something else also is equally an impediment and an evil to the constitution of plants. So then that which is a hindrance to the intelligence is an evil to the intelligent nature. Apply all these things then to thyself. Does pain or sensuous pleasure affect thee? The senses will look to that.- Has any obstacle opposed thee in thy efforts towards an object? if indeed thou wast making this effort absolutely (unconditionally, or without any reservation), certainly this obstacle is an evil to thee considered as a rational animal. But if thou takest into consideration the usual course of things, thou hast not yet been injured nor even impeded. The things however which are proper to the understanding no other man is used to impede, for neither fire, nor iron, nor tyrant, nor abuse, touches it in any way. When it has been made a sphere, it continues a sphere.