‘When Lear cries, ‘Is there any cause in nature that makes these hard hearts?’, we could reply, on one level, yes – a defect in the right prefrontal cortex. But that just illuminates the fact that cruelty does not exist in ‘nature’: only humans with their left prefrontal cortex have the capacity for deliberate malice. But then only humans, with their right prefrontal cortex, are capable of compassion.’ Iain McGilchrist