Increasing secularism during the 18th century Enlightenment period led to the emergence of a natural concept of ‘the mind’ as a separate from the previously accepted body-soul duality. Here Dr Raj Persaud talks to award-winning historian and author of the book Soul Machine, Dr George Makari, about some of the key historical cases that contributed to this new idea, and paved the way for the cognitive-style therapies used today.