We don’t try to reason with bears or babies or lunatics because they aren’t able to respond appropriately. Why do we reason with people? Why do we try to convince them of conclusions about free will or science or causation or anything else? Because we think – for good reason – that in general people are reasonable, are moved by reasons, can adjust their behaviour and goals in the light of reasons presented to them. There is something indirectly self-refuting in arguing that people are not moved by reasons!